The document discusses various topics related to mixtures and separations:
- It identifies different types of solutions, suspensions, and colloids.
- It investigates how structure and temperature affect solubility of solids in water.
- It distinguishes among solutions, suspensions, and colloids and identifies suitable separation techniques based on differences in component properties of mixtures.
- It describes the extraction of sucrose from sugar cane.
The document discusses key concepts related to ecosystems, including energy flow, trophic levels, food chains, and food webs. It explains that the sun is the primary source of energy for ecosystems and that energy flows through trophic levels from producers to consumers. While chemical elements cycle through an ecosystem, energy is lost at each transfer between trophic levels and must constantly be replenished by the sun. Food chains and food webs illustrate the complex feeding relationships and energy transfers within an ecosystem.
This document discusses mixtures and separations. It begins by defining pure substances and mixtures. It then describes different types of mixtures, including homogeneous mixtures (solutions) and heterogeneous mixtures (suspensions and colloids). Various separation techniques are identified for different types of mixtures, such as filtration, evaporation, crystallization, distillation, and chromatography. Examples are provided to illustrate solubility, separation methods, and chromatography.
The document discusses chemical equations and reactions, including:
- Indications that a chemical reaction has occurred include evolution of energy (heat/light), production of a gas, and color change.
- Chemical equations must represent known facts, contain correct formulas, and satisfy the law of conservation of mass.
- The arrow in an equation signifies a reaction occurring. Equations can show reversible reactions with double arrows.
- Types of chemical reactions include synthesis, decomposition, single-displacement, double-displacement, and combustion.
- The activity series lists elements in order of their reactivity based on displacement reactions, and can predict if a reaction will occur.
Chapter 15.1 : Properties of Acids and BasesChris Foltz
This document discusses the properties and nomenclature of acids and bases. It defines acids as substances that increase the hydrogen ion concentration in aqueous solutions, and bases as substances that increase the hydroxide ion concentration. Strong acids fully ionize in water, producing hydronium ions, while weak acids only partially ionize. Common strong acids include sulfuric acid and nitric acid. Common bases, such as sodium hydroxide, fully dissociate in water to produce hydroxide ions. The document also provides examples of uses for several acids in industry and food processing.
This document discusses properties of aqueous solutions and acid-base reactions. It describes how ionic compounds and electrolytes dissolve in water, forming ions that are solvated. Precipitation reactions that form insoluble products are explained. Strong and weak acids and bases are defined, and neutralization reactions that produce salts and water are covered. Some acid-base reactions evolve gas as one of the products.
This document defines acids, bases, and salts according to three theories:
1) Arrhenius defines acids as substances that yield hydrogen ions in water and bases as substances that yield hydroxide ions in water. Neutralization produces salt and water.
2) Bronsted-Lowry defines acids as proton donors and bases as proton acceptors. Neutralization involves the transfer of a proton from an acid to a base.
3) Lewis defines acids as electron pair acceptors and bases as electron pair donors. Neutralization involves the sharing of an electron pair between an acid and base.
Introduction to redox reactions
References
Tindale, Ritchie et al, 2014, Chemistry for CSEC 2nd Edition, Nelson Thornes. p156-159
Electron Transfer in Redox Reactions Todayhttps://www.sewanhakaschools.org
The document provides information about the process of photosynthesis. It explains that photosynthesis takes place in the chloroplasts of plant cells, where chlorophyll absorbs light energy and uses it to convert carbon dioxide and water into glucose and oxygen. The process involves two stages - the light-dependent reaction that uses light to produce ATP and NADPH, and the light-independent Calvin cycle that uses the ATP and NADPH to fix carbon dioxide and produce glucose. Plants appear green because chlorophyll, the pigment that absorbs light for photosynthesis, reflects green light wavelengths.
The document discusses key concepts related to ecosystems, including energy flow, trophic levels, food chains, and food webs. It explains that the sun is the primary source of energy for ecosystems and that energy flows through trophic levels from producers to consumers. While chemical elements cycle through an ecosystem, energy is lost at each transfer between trophic levels and must constantly be replenished by the sun. Food chains and food webs illustrate the complex feeding relationships and energy transfers within an ecosystem.
This document discusses mixtures and separations. It begins by defining pure substances and mixtures. It then describes different types of mixtures, including homogeneous mixtures (solutions) and heterogeneous mixtures (suspensions and colloids). Various separation techniques are identified for different types of mixtures, such as filtration, evaporation, crystallization, distillation, and chromatography. Examples are provided to illustrate solubility, separation methods, and chromatography.
The document discusses chemical equations and reactions, including:
- Indications that a chemical reaction has occurred include evolution of energy (heat/light), production of a gas, and color change.
- Chemical equations must represent known facts, contain correct formulas, and satisfy the law of conservation of mass.
- The arrow in an equation signifies a reaction occurring. Equations can show reversible reactions with double arrows.
- Types of chemical reactions include synthesis, decomposition, single-displacement, double-displacement, and combustion.
- The activity series lists elements in order of their reactivity based on displacement reactions, and can predict if a reaction will occur.
Chapter 15.1 : Properties of Acids and BasesChris Foltz
This document discusses the properties and nomenclature of acids and bases. It defines acids as substances that increase the hydrogen ion concentration in aqueous solutions, and bases as substances that increase the hydroxide ion concentration. Strong acids fully ionize in water, producing hydronium ions, while weak acids only partially ionize. Common strong acids include sulfuric acid and nitric acid. Common bases, such as sodium hydroxide, fully dissociate in water to produce hydroxide ions. The document also provides examples of uses for several acids in industry and food processing.
This document discusses properties of aqueous solutions and acid-base reactions. It describes how ionic compounds and electrolytes dissolve in water, forming ions that are solvated. Precipitation reactions that form insoluble products are explained. Strong and weak acids and bases are defined, and neutralization reactions that produce salts and water are covered. Some acid-base reactions evolve gas as one of the products.
This document defines acids, bases, and salts according to three theories:
1) Arrhenius defines acids as substances that yield hydrogen ions in water and bases as substances that yield hydroxide ions in water. Neutralization produces salt and water.
2) Bronsted-Lowry defines acids as proton donors and bases as proton acceptors. Neutralization involves the transfer of a proton from an acid to a base.
3) Lewis defines acids as electron pair acceptors and bases as electron pair donors. Neutralization involves the sharing of an electron pair between an acid and base.
Introduction to redox reactions
References
Tindale, Ritchie et al, 2014, Chemistry for CSEC 2nd Edition, Nelson Thornes. p156-159
Electron Transfer in Redox Reactions Todayhttps://www.sewanhakaschools.org
The document provides information about the process of photosynthesis. It explains that photosynthesis takes place in the chloroplasts of plant cells, where chlorophyll absorbs light energy and uses it to convert carbon dioxide and water into glucose and oxygen. The process involves two stages - the light-dependent reaction that uses light to produce ATP and NADPH, and the light-independent Calvin cycle that uses the ATP and NADPH to fix carbon dioxide and produce glucose. Plants appear green because chlorophyll, the pigment that absorbs light for photosynthesis, reflects green light wavelengths.
Water is essential for all living organisms, as living cells contain 70-95% water. Water has unique properties like being a polar liquid, having a high specific heat, heat of vaporization, and latent heat of fusion. It can perform capillary action and is a universal solvent. These properties allow water to transport nutrients within plants and cool plants through transpiration. Water is also important for agricultural productivity and plant growth.
A solution is a homogeneous mixture of two or more substances, where the solute is dispersed uniformly throughout the solvent. The solubility of a solute is dependent on temperature, pressure, and the nature of the solute and solvent. Solubility is expressed as the maximum grams of solute that will dissolve per 100 grams of solvent. Colligative properties, such as boiling point elevation and freezing point depression, depend only on the number of solute particles and not their identity.
A pure substance consists of only one substance, while a mixture contains two or more substances not chemically combined. The purity of a substance can be determined by testing its fixed melting and boiling points or using chromatography. Various separation methods exist that separate substances based on differences in their physical properties such as solubility, boiling points, magnetism, and ability to sublime. Common separation methods include filtration, crystallization, distillation, chromatography, and magnetic attraction.
This document discusses chemistry of solutions. It defines key terms like solute, solvent and solution. It explains that a solution is a homogeneous mixture of two or more substances. The solute is dispersed uniformly throughout the solvent. Factors that affect solubility are also discussed, like temperature, pressure, molecular size and polarity. Henry's law is introduced, which states that the solubility of a gas is directly proportional to its partial pressure.
This document discusses the properties of water molecules and how those properties allow water to serve important functions. It covers the following key points:
1) Water molecules are polar due to their molecular structure, and they form hydrogen bonds between each other. This explains water's cohesive, adhesive, thermal, and solvent properties.
2) Substances can be either hydrophilic ("water-loving") if they are polar, or hydrophobic ("water-fearing") if they are nonpolar. Polar substances like glucose and phospholipids can dissolve in water due to hydrogen bonding.
3) Water has high specific heat and heat of vaporization, allowing it to effectively absorb and release heat. This contributes to temperature regulation
The document outlines key concepts in electrochemistry including:
1. Electrolysis involves using electricity to break down ionic compounds or solutions into their components. It occurs when ions are able to move freely in molten or aqueous states.
2. During electrolysis, cations move to the cathode where they gain electrons and undergo reduction reactions. Anions move to the anode where they lose electrons and undergo oxidation reactions.
3. The electrolysis of molten ionic compounds produces metals at the cathode and non-metals at the anode. Electrolysis of aqueous solutions can produce hydrogen and oxygen from water or discharge other ions depending on their reactivity.
This document discusses formal charge and how to calculate it in Lewis structures. It provides examples of calculating formal charges for different Lewis structures of the thiocyanate ion. The preferred structure is the one that puts the negative charge on the most electronegative atom (nitrogen) and has the fewest formal charges of largest magnitude. A practice problem is then given to draw the Lewis structures of the cyanate ion and identify the preferred structure based on these guidelines.
Ventilation refers to the process of moving air in and out of the lungs. Respiration is the cellular process of gas exchange that occurs in the lungs, where oxygen diffuses into the blood and carbon dioxide diffuses out. The ventilation system, which includes the trachea, lungs, bronchi, bronchioles and alveoli, facilitates gas exchange through its features that maximize surface area for diffusion and maintain concentration gradients between the alveoli and blood. The diaphragm, intercostal muscles and abdominal muscles work together to change the volume and pressure of the lungs during breathing to ventilate air in and out.
Community interactions such as competition, predation, and symbiosis shape ecosystems. Competition occurs when organisms seek the same resources, leading to winners and losers. Predation involves a predator killing and eating prey. Symbiosis describes close relationships between species, including mutualism where both benefit, commensalism where one benefits without affecting the other, and parasitism where one harms the host. Ecosystems constantly change through ecological succession as disturbances allow new species to establish over time through primary succession on new surfaces and secondary succession following disturbances.
The document discusses different types of chemical bonds including ionic bonds and covalent bonds. Ionic bonds involve the transfer of electrons between metals and non-metals, resulting in ionic compounds with high melting and boiling points that conduct electricity when melted or in solution. Covalent bonds involve the sharing of electrons between non-metal atoms, resulting in molecules with low melting and boiling points that do not conduct electricity. The document also discusses metallic bonding and how metal atoms are held together by valence electrons that are delocalized throughout the structure.
This document discusses key properties and concepts related to solutions. It defines a solution as being made up of a solvent and one or more solutes. The solvent is the substance that exists in the greatest quantity, while solutes are all other substances present. Solutions can be solid, liquid or gas depending on the state of the solvent. The document also discusses concentration, solubility, factors that affect solubility like temperature and pressure, and how to increase the rate at which a solute dissolves.
This document provides an overview of a PowerPoint presentation on structure and bonding for GCSE chemistry students. It introduces ionic bonding, metallic bonding, and covalent bonding. The document explains that the presentation covers how different types of chemical bonding affect the physical properties of elements and compounds. It also provides website information for additional resources on this topic.
This is a summary of the topic "Energy changes" in the GCE O levels subject: Chemistry. Students taking either the combined science (chemistry/physics) or pure chemistry will find this useful. These slides are prepared according to the learning outcomes required by the examinations board.
This document discusses acids and alkalis. It defines acids as substances that produce hydrogen ions in water, and provides examples like hydrochloric acid. Acids have properties like a sour taste, turning litmus red, and reacting with metals and carbonates. Alkalis are defined as metal oxides or hydroxides soluble in water, with examples like sodium hydroxide. Alkalis have properties like a bitter taste, turning litmus blue, and reacting with acids. The document also describes how acids and alkalis neutralize each other to form salts and water.
The document outlines an chemistry class where students will learn about stoichiometry, mole ratios, and balancing chemical equations. Students are instructed to take notes on mole ratios and balancing equations using examples worked through in class. For homework, students are asked to finish practice problems on these topics in preparation for an upcoming exam.
The document discusses various methods of purifying substances, including filtration, crystallization, and evaporation. It provides details on the principles and procedures of these purification techniques. Filtration is used to separate insoluble solids from liquids or solutions. Crystallization produces pure solids from solutions and is used if the solid decomposes upon strong heating. Evaporation removes the solvent from a solution, leaving behind the pure solid, and is used if the solid does not decompose with heat.
An overview of the main factors making up the non-living (abiotic) environment of the plant. The requirements of the plant and the effects of absnormal condtions are also mentioned briefly.
Changes in community structure affect and are influenced by organisms. The document discusses various topics related to communities and ecosystems, including trophic levels in food webs, energy conversion rates, stable ecosystem emergence based on climate, and the influence of disturbance on ecosystem structure and change rates. It also provides guidance on understandings, applications, and skills related to these concepts.
This document discusses the properties and reactions of acids and bases. It states that acids have a sour taste and cause color changes in indicators like litmus. Acids react with metals to produce hydrogen gas and with carbonates to produce carbon dioxide gas. Bases have a bitter taste and feel slippery. Strong acids and bases fully dissociate in water while weak acids and bases only partially dissociate. The Bronsted-Lowry theory defines acids as proton donors and bases as proton acceptors. Water can act as both an acid and a base depending on the reaction.
Organic compounds are almost 60% of all compounds. because of carbons tendency to form a compound as it has more than1 electron(4electrons) to form covallent compounds. SO a wide range of everything we eat is formed from carbon and hydrogen, which is the second important element to form organic compounds.
A mixture is when two or more substances are mixed together without chemically combining. Mixtures can be separated into their original substances using physical means. Some common ways to separate mixtures include magnetism, filtration, sieving, extraction, and chromatography. Magnetism uses magnets to separate mixtures where one substance is magnetic. Filtration separates solids from liquids by passing the mixture through a porous filter. Sieving separates substances of different sizes by passing the mixture through a sieve with tiny holes. Extraction separates soluble and insoluble substances by dissolving one in a solvent and filtering out the other.
To make magnetic art, place magnets under paper and sprinkle iron filings on top to see the shape of the magnetic field. Gently spread the filings to fill the space, then draw or photograph the pattern. While electricity did not move the filings in a circuit as predicted, magnets were able to demonstrate magnetic fields by arranging the filings.
Water is essential for all living organisms, as living cells contain 70-95% water. Water has unique properties like being a polar liquid, having a high specific heat, heat of vaporization, and latent heat of fusion. It can perform capillary action and is a universal solvent. These properties allow water to transport nutrients within plants and cool plants through transpiration. Water is also important for agricultural productivity and plant growth.
A solution is a homogeneous mixture of two or more substances, where the solute is dispersed uniformly throughout the solvent. The solubility of a solute is dependent on temperature, pressure, and the nature of the solute and solvent. Solubility is expressed as the maximum grams of solute that will dissolve per 100 grams of solvent. Colligative properties, such as boiling point elevation and freezing point depression, depend only on the number of solute particles and not their identity.
A pure substance consists of only one substance, while a mixture contains two or more substances not chemically combined. The purity of a substance can be determined by testing its fixed melting and boiling points or using chromatography. Various separation methods exist that separate substances based on differences in their physical properties such as solubility, boiling points, magnetism, and ability to sublime. Common separation methods include filtration, crystallization, distillation, chromatography, and magnetic attraction.
This document discusses chemistry of solutions. It defines key terms like solute, solvent and solution. It explains that a solution is a homogeneous mixture of two or more substances. The solute is dispersed uniformly throughout the solvent. Factors that affect solubility are also discussed, like temperature, pressure, molecular size and polarity. Henry's law is introduced, which states that the solubility of a gas is directly proportional to its partial pressure.
This document discusses the properties of water molecules and how those properties allow water to serve important functions. It covers the following key points:
1) Water molecules are polar due to their molecular structure, and they form hydrogen bonds between each other. This explains water's cohesive, adhesive, thermal, and solvent properties.
2) Substances can be either hydrophilic ("water-loving") if they are polar, or hydrophobic ("water-fearing") if they are nonpolar. Polar substances like glucose and phospholipids can dissolve in water due to hydrogen bonding.
3) Water has high specific heat and heat of vaporization, allowing it to effectively absorb and release heat. This contributes to temperature regulation
The document outlines key concepts in electrochemistry including:
1. Electrolysis involves using electricity to break down ionic compounds or solutions into their components. It occurs when ions are able to move freely in molten or aqueous states.
2. During electrolysis, cations move to the cathode where they gain electrons and undergo reduction reactions. Anions move to the anode where they lose electrons and undergo oxidation reactions.
3. The electrolysis of molten ionic compounds produces metals at the cathode and non-metals at the anode. Electrolysis of aqueous solutions can produce hydrogen and oxygen from water or discharge other ions depending on their reactivity.
This document discusses formal charge and how to calculate it in Lewis structures. It provides examples of calculating formal charges for different Lewis structures of the thiocyanate ion. The preferred structure is the one that puts the negative charge on the most electronegative atom (nitrogen) and has the fewest formal charges of largest magnitude. A practice problem is then given to draw the Lewis structures of the cyanate ion and identify the preferred structure based on these guidelines.
Ventilation refers to the process of moving air in and out of the lungs. Respiration is the cellular process of gas exchange that occurs in the lungs, where oxygen diffuses into the blood and carbon dioxide diffuses out. The ventilation system, which includes the trachea, lungs, bronchi, bronchioles and alveoli, facilitates gas exchange through its features that maximize surface area for diffusion and maintain concentration gradients between the alveoli and blood. The diaphragm, intercostal muscles and abdominal muscles work together to change the volume and pressure of the lungs during breathing to ventilate air in and out.
Community interactions such as competition, predation, and symbiosis shape ecosystems. Competition occurs when organisms seek the same resources, leading to winners and losers. Predation involves a predator killing and eating prey. Symbiosis describes close relationships between species, including mutualism where both benefit, commensalism where one benefits without affecting the other, and parasitism where one harms the host. Ecosystems constantly change through ecological succession as disturbances allow new species to establish over time through primary succession on new surfaces and secondary succession following disturbances.
The document discusses different types of chemical bonds including ionic bonds and covalent bonds. Ionic bonds involve the transfer of electrons between metals and non-metals, resulting in ionic compounds with high melting and boiling points that conduct electricity when melted or in solution. Covalent bonds involve the sharing of electrons between non-metal atoms, resulting in molecules with low melting and boiling points that do not conduct electricity. The document also discusses metallic bonding and how metal atoms are held together by valence electrons that are delocalized throughout the structure.
This document discusses key properties and concepts related to solutions. It defines a solution as being made up of a solvent and one or more solutes. The solvent is the substance that exists in the greatest quantity, while solutes are all other substances present. Solutions can be solid, liquid or gas depending on the state of the solvent. The document also discusses concentration, solubility, factors that affect solubility like temperature and pressure, and how to increase the rate at which a solute dissolves.
This document provides an overview of a PowerPoint presentation on structure and bonding for GCSE chemistry students. It introduces ionic bonding, metallic bonding, and covalent bonding. The document explains that the presentation covers how different types of chemical bonding affect the physical properties of elements and compounds. It also provides website information for additional resources on this topic.
This is a summary of the topic "Energy changes" in the GCE O levels subject: Chemistry. Students taking either the combined science (chemistry/physics) or pure chemistry will find this useful. These slides are prepared according to the learning outcomes required by the examinations board.
This document discusses acids and alkalis. It defines acids as substances that produce hydrogen ions in water, and provides examples like hydrochloric acid. Acids have properties like a sour taste, turning litmus red, and reacting with metals and carbonates. Alkalis are defined as metal oxides or hydroxides soluble in water, with examples like sodium hydroxide. Alkalis have properties like a bitter taste, turning litmus blue, and reacting with acids. The document also describes how acids and alkalis neutralize each other to form salts and water.
The document outlines an chemistry class where students will learn about stoichiometry, mole ratios, and balancing chemical equations. Students are instructed to take notes on mole ratios and balancing equations using examples worked through in class. For homework, students are asked to finish practice problems on these topics in preparation for an upcoming exam.
The document discusses various methods of purifying substances, including filtration, crystallization, and evaporation. It provides details on the principles and procedures of these purification techniques. Filtration is used to separate insoluble solids from liquids or solutions. Crystallization produces pure solids from solutions and is used if the solid decomposes upon strong heating. Evaporation removes the solvent from a solution, leaving behind the pure solid, and is used if the solid does not decompose with heat.
An overview of the main factors making up the non-living (abiotic) environment of the plant. The requirements of the plant and the effects of absnormal condtions are also mentioned briefly.
Changes in community structure affect and are influenced by organisms. The document discusses various topics related to communities and ecosystems, including trophic levels in food webs, energy conversion rates, stable ecosystem emergence based on climate, and the influence of disturbance on ecosystem structure and change rates. It also provides guidance on understandings, applications, and skills related to these concepts.
This document discusses the properties and reactions of acids and bases. It states that acids have a sour taste and cause color changes in indicators like litmus. Acids react with metals to produce hydrogen gas and with carbonates to produce carbon dioxide gas. Bases have a bitter taste and feel slippery. Strong acids and bases fully dissociate in water while weak acids and bases only partially dissociate. The Bronsted-Lowry theory defines acids as proton donors and bases as proton acceptors. Water can act as both an acid and a base depending on the reaction.
Organic compounds are almost 60% of all compounds. because of carbons tendency to form a compound as it has more than1 electron(4electrons) to form covallent compounds. SO a wide range of everything we eat is formed from carbon and hydrogen, which is the second important element to form organic compounds.
A mixture is when two or more substances are mixed together without chemically combining. Mixtures can be separated into their original substances using physical means. Some common ways to separate mixtures include magnetism, filtration, sieving, extraction, and chromatography. Magnetism uses magnets to separate mixtures where one substance is magnetic. Filtration separates solids from liquids by passing the mixture through a porous filter. Sieving separates substances of different sizes by passing the mixture through a sieve with tiny holes. Extraction separates soluble and insoluble substances by dissolving one in a solvent and filtering out the other.
To make magnetic art, place magnets under paper and sprinkle iron filings on top to see the shape of the magnetic field. Gently spread the filings to fill the space, then draw or photograph the pattern. While electricity did not move the filings in a circuit as predicted, magnets were able to demonstrate magnetic fields by arranging the filings.
This document discusses different techniques for separating mixtures: magnetic attraction, filtration, evaporation, distillation, and paper chromatography. It explains that mixtures contain two or more substances and can be easily separated. The techniques are then defined: magnetic attraction separates mixtures containing magnetic materials; filtration separates insoluble solids from liquids; evaporation separates dissolved solids from liquids; distillation separates liquid mixtures with different boiling points; and paper chromatography separates components in essential oils. Examples of each technique are provided.
What happens when matter goes through a physicalsafa-medaney
When matter undergoes a physical change, it changes shape or size but retains its chemical composition. Physical changes include tearing paper, freezing water into ice, and stretching a rubber band. These processes change the appearance of the matter but not its identity - the paper, water, and rubber band can be returned to their original state. Chemical changes, like burning paper or matches, cannot be reversed as the matter is transformed into different substances. Mixtures and solutions involve combining different types of matter and can be separated using methods like picking objects out of mixtures, magnets, filtration, or evaporation.
The document provides instructions for separating a mixture of sand, salt, iron filings, and benzoic acid by developing and following a plan that utilizes different properties of the substances and available equipment such as beakers, distilled water, a hot plate, filter paper, and a magnet to separate and measure the mass of each recovered substance. Safety precautions are outlined including wearing goggles and gloves when handling benzoic acid and using caution with hot equipment. Students must get their separation plan approved by a teacher before beginning the experiment.
Simple techniques of separating mixturesAnand Kumar
This document provides information on techniques for separating mixtures. It discusses several methods including sedimentation and decantation, filtration, evaporation, distillation, crystallization, sublimation, chromatography, centrifugation and solvent extraction. The document is intended for a 9th grade science class and aims to teach students how to select the appropriate separation method based on the components of a mixture. It includes links to videos demonstrating each technique.
This document discusses various methods for separating mixtures, including magnetism, filtration, sieving, extraction, evaporation, distillation, and sedimentation. It provides examples of how each method can be used to separate common mixtures like sand and water, nails and wood chips, coffee beans and grounds. The key methods are using magnetic, physical, or chemical properties to differentiate components, then employing tools like filters, sieves, solvents, heat, or settling to complete the separation.
Data Logger: Melting and Freezing Points of NaphthaleneRochelle Ning
1. The document describes an experiment to determine the melting and freezing points of naphthalene using a data logger. Students heated naphthalene from 60°C to 90°C and recorded the temperature changes, observing the melting point at 80°C. They then cooled liquefied naphthalene and again recorded temperatures, observing the freezing point also at 80°C.
2. The document discusses engaging, empowering and enhancing students' understanding of phase changes by asking probing questions and having them interpret graphs of temperature over time. It emphasizes how data loggers make laboratory experiments more efficient and informative for learning science concepts.
This document discusses enthalpy changes and exothermic and endothermic reactions. It defines exothermic reactions as reactions where heat is given out to the surroundings, while endothermic reactions absorb heat from the surroundings. The amount of heat given out or absorbed during a reaction is called the enthalpy change. Whether a reaction is exothermic or endothermic depends on whether bond breaking absorbs more energy than bond forming releases, or vice versa.
The document discusses various topics related to matter and chemical changes. It defines elements and compounds, explains that compounds can undergo chemical changes while elements cannot, and states that the law of conservation of mass means the mass of reactants equals the mass of products in a chemical reaction. It also distinguishes physical and chemical changes, noting that only chemical changes alter the composition of matter.
This document discusses magnetic separation processes. It begins with an introduction explaining that magnetic separation involves using magnetic forces to extract magnetically susceptible materials from mixtures. It then describes different types of magnetic separators including Edison separators, ball and Norton separators, magnetic drum separators, roller separators, gravity feed separators, and magnetic coolant separators. It explains how each works and their applications in industries like mining, ceramics, chemicals, food, and more. The key advantages of magnetic separation are that it provides an effective means of separating and concentrating magnetic materials from gangue.
This document discusses magnetic separators, including their working principles, construction, types, and industrial applications. Magnetic separators use magnetic fields to remove magnetic materials from a feed or concentrate ore by exploiting differences in magnetic properties. Common types include drum magnets, which are used in industries like sugar, cement, and chemicals to remove fine iron; plate magnets, which remove tramp iron from glass, food, and textile industries; and pipeline magnets, which purify liquid lines. Magnetic separators have a variety of industrial uses including product purification and protecting downstream equipment from magnetic contamination.
C06 concentration of solutions and volumetric analysisChemrcwss
This document provides information on concentration of solutions and volumetric analysis. It defines key terms like solute, solvent, concentrated and dilute solutions. It explains how to calculate concentration in g/dm3 and mol/dm3 and includes examples. The document also describes the process of volumetric analysis including using a pipette and burette accurately. It explains how to perform and record a titration experiment to determine the concentration of an unknown acid solution.
This document discusses different types of magnetic separators used to separate minerals based on their magnetic properties. It describes how materials can be classified as diamagnetic or paramagnetic and provides examples of paramagnetic minerals. Several important types of magnetic separators are then outlined, including magnetic drum separators, Ball Norton separators, roller type separators, gravity feed magnets, and wet drum separators. Their basic workings and industrial applications are summarized for each type.
The document summarizes key points about cooking methods and chemistry:
- It discusses two methods of tenderizing meat: hanging meat to age and using mechanical or chemical actions like beating or marinating.
- It explains how a pressure cooker works by raising the pressure above atmospheric pressure, increasing the boiling point of water and allowing food to cook faster while retaining more nutrients.
- It identifies starch and protein as major constituents in flour and describes how their structures are altered through processes like gelatinization and denaturation during cooking.
This document discusses mixtures and separation techniques. It defines pure substances and mixtures, and describes different types of mixtures like solutions, suspensions, and colloids. Several physical separation methods are described, including filtration, evaporation, crystallization, sublimation, distillation, fractional distillation, use of a separating funnel, and chromatography. These techniques separate mixtures based on differences in properties of the components like solubility, boiling point, and polarity. The document also provides examples to illustrate key concepts and separation processes.
Important questions CLASS 9 IS MATTER AROUND US PUREthesaver
This document discusses questions related to pure substances and mixtures. It provides answers to questions about classifying mixtures as homogeneous or heterogeneous, identifying solutions, distinguishing between physical and chemical changes, and techniques for separating mixtures like distillation, crystallization, chromatography, and centrifugation. Key topics covered include properties of pure substances and mixtures, types of mixtures, solubility and saturation, and separation methods for mixtures and solutions.
This document provides an introduction to chemistry and the scientific method. It discusses chemistry as a science for the 21st century and how it relates to areas like health, energy, materials, food and more. The document then covers topics like the study of chemistry on both the microscopic and macroscopic levels, the scientific method, atomic theory, classification of matter, states of matter, mixtures and pure substances including elements and compounds. It also discusses physical and chemical properties and changes.
CSEC Chemistry Review - Mixtures and CompoundsKevin Small
www.knowledgescroll.com
After Viewing This Presentation You Should Be Able to:
Distinguish between pure substances, mixtures and
compounds.
Show examples common mixtures.
Discuss the various separation techniques of mixtures based on the different properties of the components.
The document discusses key concepts in chemistry including:
1) Matter can be classified as having physical or chemical properties, with physical changes altering physical properties but not chemical composition and chemical changes resulting in new substances.
2) Elements are the fundamental components of matter and are represented by atomic symbols on the periodic table, while compounds are formed by chemical bonds between different elements represented by chemical formulas.
3) Most materials are mixtures that combine substances without chemical change, whereas pure substances consist of only one type of element or compound.
This document discusses the classification of matter into elements, compounds, and mixtures. It defines elements as the simplest form of matter that cannot be broken down further through chemical reactions. Compounds are formed via chemical reactions and consist of two or more chemically bonded elements. Mixtures are physical combinations of elements and/or compounds that are not chemically bonded and can be separated using physical means. The document provides examples and properties to distinguish among these three classifications of matter.
The document discusses various properties of water including its composition, structure, and ability to dissolve many substances. It explains that water is a compound made of hydrogen and oxygen atoms, and it can act as both an acid and a base by producing H+ and OH- ions. Water has a high capacity for dissolving substances due to its polar nature. The document also covers topics like solvents, solutions, factors affecting solubility, and hardness of water. It provides examples and videos for additional explanation.
The document discusses surface chemistry concepts including adsorption, catalysis, and colloids. It provides definitions and examples of key terms. For adsorption, it defines adsorbate and adsorbent, and gives examples of physical and chemical adsorption. For catalysis, it distinguishes between homogeneous and heterogeneous catalysis, and discusses properties of solid catalysts including activity and selectivity. It also provides examples of enzyme catalysis. Finally, it defines colloids and classifies them based on the physical state of the dispersed and dispersion phases.
1) A chemical reaction is a process where one or more new substances are formed. Chemical equations represent reactions using symbols for reactants and products.
2) Balanced chemical equations ensure the same number and type of atoms for each element on both sides of the reaction arrow.
3) Common reaction types include combination, decomposition, displacement, and double displacement. Combination reactions form one product from two or more reactants while decomposition reactions break down one reactant into multiple products.
Class 10 chemical reactions and equationssarunkumar31
Types of reactions, Redox reactions, Reaction between acid and metal, Types of decomposition reaction, corrosion and rancidity.Acidic and basic nature of oxide, prevention method of corrosion.
Notes main points FROM THE CHAPTER IS MATTER AREOUND US PUREthesaver
1. Matter can exist as pure substances, mixtures, or compounds. Pure substances are either elements or compounds that have a uniform composition. Mixtures are combinations of substances that retain their individual chemical identities.
2. Mixtures can be either homogeneous, with a uniform composition, or heterogeneous, with a non-uniform composition. Common homogeneous mixtures include solutions and alloys. Common heterogeneous mixtures include mixtures of sand and sugar.
3. There are various techniques that can be used to separate mixtures into their individual components, including filtration, centrifugation, chromatography, distillation, crystallization, and more. The appropriate separation technique depends on the types of substances involved.
Investigating The Kinetics Of The Reaction Between Iodide...Jennifer Reither
This document describes plans to investigate the kinetics of the reaction between iodide ions and peroxodisulphate ions. The author will conduct experiments changing the concentration of iodide ions, peroxodisulphate ions, and the temperature of the solution. This will help determine the reaction order and activation enthalpy. The effect of temperature on reaction rate is also discussed, with increased temperature causing faster particle collisions and more reactions surmounting the activation enthalpy barrier.
Elements, compounds, and mixtures are discussed. Elements are pure substances that cannot be broken down further, while compounds are formed when two or more elements are chemically bonded together. Compounds have unique properties and can be broken down into their constituent elements through chemical or electrolytic processes. Elements are classified as metals, nonmetals, or metalloids based on their physical properties such as conductivity.
This document discusses physical and chemical changes through examples. It describes how rust forms on iron when exposed to oxygen and water, which is a chemical change represented by the equation Fe + O2 + H2O → Fe2O3. A physical change is also discussed, where burning magnesium ribbon leaves an ash that forms an acidic solution when mixed with water. Experiments are presented on burning magnesium ribbon, the reaction of iron and copper sulfate solution, and using limewater to test for carbon dioxide.
Here are the types of mixtures for the given examples:
1. Sugar dissolved in water - Solution
2. Mixture of ethyl alcohol and water - Solution
3. Mixture of salt and sand - Heterogeneous mixture (Mechanical mixture)
4. Iron filings, mongo seeds and salt mixture - Heterogeneous mixture (Mechanical mixture)
The first two examples involve dissolving of substances and forming a homogeneous mixture at the molecular level, so they are solutions.
The last two examples involve mechanical mixing of substances without dissolving and remaining as distinguishable parts, so they are heterogeneous mixtures.
This document provides an introduction to chemistry, including defining matter and its three states (solid, liquid, gas). It discusses the particles that compose matter (atoms, molecules, ions) and their properties. Methods for separating mixtures are also outlined, such as filtration, distillation, evaporation, and chromatography. Consumer products often contain mixtures to appeal to customers, with examples given of household cleaning supplies and personal care items.
This document discusses the classification and states of matter. It defines substances as samples of matter with uniform physical and chemical properties throughout. Substances can exist in solid, liquid, or gas states depending on the energy and spacing of their particles. Matter is classified as elements, compounds, or mixtures. Elements consist of only one type of atom and cannot be broken down further. Compounds are formed from two or more elements and can be broken down into their component elements. Mixtures contain two or more substances but are not chemically combined. Mixtures can be homogeneous, with uniform composition, or heterogeneous. The document then discusses various states of matter and techniques for separating mixtures.
Matter is anything that has mass and takes up space. It is composed of atoms, which contain protons, neutrons, and electrons. Elements are pure substances made of only one type of atom, while compounds are made of two or more elements chemically bonded together. Mixtures contain different substances mixed together but not chemically combined. The three main states of matter are solids, liquids, and gases. Chemical and physical properties can be used to describe and identify matter.
This document discusses solutions and solubility. It defines key terms like solution, solute, solvent, concentration and molarity. It explains that a solution is a homogeneous mixture of two or more substances, with a solute dissolved in a solvent. Concentration refers to the amount of solute per unit of solvent. Molarity specifically refers to moles of solute per liter of solution. The document also discusses factors that affect solubility like temperature, pressure and polarity. It covers separation techniques like distillation, filtration and chromatography. Finally, it discusses emulsions, surfactants and how soap works to emulsify oils.
This document discusses physical and chemical changes in various processes like photosynthesis, dissolving sugar in water, burning of coal, and digestion of food. It also provides examples of chemical changes like setting of curd and burning of wood versus the physical change of cutting wood. The document describes how crystals of copper sulfate are prepared using crystallization. It explains how painting prevents rusting of iron by creating a barrier between the iron, oxygen, and water. Rusting is faster in coastal areas due to higher humidity levels compared to deserts.
This chapter discusses rates of reactions. It defines rate of reaction as how fast or slow a reaction is taking place. There are three main ways to measure rate of reaction: measuring time taken for reaction to complete, measuring amount of product formed per unit time, and measuring amount of reactant used up or remaining per unit time. The rate of reaction is affected by several factors like temperature, concentration, particle size, catalyst, and pressure. Temperature has the greatest effect as increasing temperature increases the kinetic energy of particles, leading to more successful collisions. Catalysts are substances that increase reaction rate without being used up in the reaction. They provide alternative reaction pathways or increase surface area for contact between reactants.
This chapter discusses the mole concept, including defining the mole, deriving empirical and molecular formulas, stating Avogadro's Law, and applying the mole concept to ionic and molecular equations. It introduces the mole as the amount of substance containing 6x1023 particles. It provides examples of how to determine the empirical formula, molecular formula, and formula of a compound from composition data. It also discusses molar volume of gases and limiting reactants. Worked examples are included for many of these concepts.
The document is a chapter about elements and compounds from a chemistry textbook. It contains the following key points in 3 sentences:
The chapter defines elements as substances that cannot be broken down further, while compounds are substances made of two or more elements chemically bonded together. It explains that elements are represented by chemical symbols and compounds by chemical formulas showing the ratios of atoms present. The chapter also discusses writing and balancing chemical equations to represent chemical reactions in terms of reactants and products.
C03 relative masses of atoms and moleculesChemrcwss
The document discusses relative atomic mass and relative molecular mass. It defines relative atomic mass as the average mass of an atom compared to 1/12 the mass of one carbon-12 atom. Relative molecular mass is defined similarly on a molecular level. Examples are provided for calculating relative atomic masses from the periodic table and relative molecular masses by adding atomic masses. Percentage composition, yield, and purity calculations involving relative masses are also illustrated.
This document provides an overview of chemical bonding and macromolecular structures. It discusses the different types of bonds including ionic bonds formed by transfer of electrons between metals and non-metals, and covalent bonds formed by sharing of electrons between non-metals. Ionic compounds have high melting and boiling points and conduct electricity when molten or dissolved, while covalent compounds have low melting and boiling points and do not conduct electricity. It also describes macromolecular and metallic structures, noting that macromolecules have very high melting points due to their large size, while metals form lattice structures with positive ions in a sea of delocalized electrons, making them malleable.
This chapter discusses the properties and reactions of non-metals. It describes the differences between metals and non-metals, and provides details on the structure and properties of common non-metals like hydrogen, oxygen, nitrogen, carbon, chlorine and sulfur. It also explains methods for producing important compounds from non-metals like sulfuric acid, chlorine and ammonia.
This chapter discusses the extraction of metals from ores. It explains that metals higher in the reactivity series like sodium and aluminium are extracted via electrolysis, while metals lower in the series like iron and copper are extracted by reduction with carbon. The extraction of aluminium, iron, and the uses and corrosion of these metals are described in detail. The chapter also covers how metals are protected from corrosion through various methods like painting, galvanization, and cathodic protection.
This chapter discusses the physical and chemical properties of metals. Metals are usually hard, shiny, malleable and ductile. They are good conductors of heat and electricity. Chemically, metals form positive ions and react with acids, oxygen, water and steam to form salts and release hydrogen gas. The reactivity of metals can be predicted based on their reactivity series, with more reactive metals displacing less reactive ones from their compounds. Alloys are stronger than pure metals due to disrupted atomic layers.
Here are the answers:
1. (a) Carbon monoxide, methane
(b) Sulphur dioxide, nitrogen oxides
2. (a) Sulphur dioxide
(b) Methane
(c) Carbon monoxide
(d) Carbon monoxide, nitrogen oxides
3. (a) O3
(b) (i) A layer of ozone surrounds the Earth at high altitudes and protects us from the harmful radiation of the Sun.
(ii) At ground level, ozone is a harmful pollutant that causes irritation to the eyes and throat. It also causes breathing difficulties and asthma attacks.
This chapter discusses polymers, which are large molecules composed of repeating structural units called monomers. It covers the different types of polymerization reactions, examples of natural and synthetic polymers, and their properties and uses. The chapter also addresses issues with plastic waste and ways to reduce pollution from plastics.
This chapter discusses sources of carbon compounds. It describes fossil fuels like coal, petroleum and natural gas, which are formed from remains of ancient plants and animals. Natural gas is a cleaner burning fuel than coal. Petroleum is refined using fractional distillation to separate it into fractions with different boiling points. Cracking converts heavier fractions into lighter, more useful ones. Fossil fuels are finite, so alternatives like solar, wind and biodiesel from algae are being explored.
Here are the answers to the quick check questions:
1. Raw materials required for ethanol production by fermentation are carbohydrates such as starch or sugar, water, yeast and a source of enzymes.
2. The chemical equations for the fermentation of sugar are:
C6H12O6 → 2C2H5OH + 2CO2
Glucose → Ethanol + Carbon dioxide
This document provides an overview of hydrocarbons and outlines the key learning outcomes of Chapter 15. It discusses the bonding ability of carbon and how carbon can form chains, branches, and rings. It then focuses on two major classes of hydrocarbons - alkanes and alkenes. For each, it defines the homologous series, provides examples, and describes their structures, properties, reactions, and uses. It also introduces topics like isomerism that are important for understanding organic compounds.
This document outlines the process of qualitative analysis, which involves identifying unknown substances by determining the cations and anions present. It describes preliminary observations, tests to identify common gases, and reactions using sodium hydroxide and ammonia solutions to identify cations based on the color and solubility of precipitates formed. The goal is to draw conclusions and identify the unknown based on a systematic analysis and recording of observations from chemical tests.
The document outlines learning outcomes for a chapter on electrochemistry. It will describe investigations into classifying substances as conductors or non-conductors, distinguish between metallic and electrolytic conduction, define key terms like electrolysis, electrodes, and ions. It will also cover predicting reactions and products of electrolysis, calculating quantities produced using Faraday's constant, and discussing industrial applications of electrolysis.
This hymn expresses the singer's faith and trust in God despite not knowing or understanding fully why God chose them or how their faith was imparted. Over four verses, the singer acknowledges not knowing why God showed grace to them, how their faith was given or peace was brought to their heart, how the Spirit works, or when Jesus may return. However, the refrain emphasizes that they know and are convinced of who they have believed in and that God will keep safe what is committed to him until that final day.
- J.J. Thomson's plum pudding model of the atom was modified based on evidence from experiments by Rutherford, Geiger, Marsden, and Bohr.
- In the gold foil experiment, Geiger and Marsden observed some alpha particles deflected at high angles from a thin gold foil, inconsistent with Thomson's model but evidence for a small, dense nucleus.
- Bohr incorporated Planck's quantum theory to explain the stability of atoms, suggesting electrons occupy discrete energy levels and jump between them.
Ancient Greek philosophers proposed early models of atoms as fundamental elements like earth, air, fire and water. In the 17th century, Robert Boyle questioned these models and advocated experimentation over philosophy. John Dalton proposed atoms as indivisible, identical spheres that combine to form compounds. J.J. Thompson's "plum pudding" model depicted atoms as positive and negative charges. However, experiments by Ernest Rutherford, Hans Geiger and Ernest Marsden found most alpha particles passed through a gold foil with few deflected, leading Rutherford to propose the planetary model of a small, dense nucleus surrounded by electrons. Later, Henry Moseley arranged elements by atomic number, James Chadwick discovered the neutral neutron in the
Dalton's original atomic theory proposed that atoms were indivisible and identical for each element. Later evidence from experiments by scientists like J.J. Thomson, Ernest Rutherford, Niels Bohr, and James Chadwick modified Dalton's theory by showing that atoms have internal structure consisting of subatomic particles and that isotopes of the same element can have different atomic masses. These discoveries helped establish modern atomic theory and understanding of the structure of atoms and nuclei.
The document summarizes the development of atomic models from Thomson's "plum pudding" model to Rutherford's nuclear model. It describes experiments by Geiger and Marsden that showed most alpha particles passed through a thin gold foil but some were deflected at large angles, inconsistent with Thomson's model. This led Rutherford to propose that the atom's mass and positive charge are concentrated in a tiny, dense nucleus with electrons in empty space around it, like planets around the sun.
A Free 200-Page eBook ~ Brain and Mind Exercise.pptxOH TEIK BIN
(A Free eBook comprising 3 Sets of Presentation of a selection of Puzzles, Brain Teasers and Thinking Problems to exercise both the mind and the Right and Left Brain. To help keep the mind and brain fit and healthy. Good for both the young and old alike.
Answers are given for all the puzzles and problems.)
With Metta,
Bro. Oh Teik Bin 🙏🤓🤔🥰
How to Manage Reception Report in Odoo 17Celine George
A business may deal with both sales and purchases occasionally. They buy things from vendors and then sell them to their customers. Such dealings can be confusing at times. Because multiple clients may inquire about the same product at the same time, after purchasing those products, customers must be assigned to them. Odoo has a tool called Reception Report that can be used to complete this assignment. By enabling this, a reception report comes automatically after confirming a receipt, from which we can assign products to orders.
A Visual Guide to 1 Samuel | A Tale of Two HeartsSteve Thomason
These slides walk through the story of 1 Samuel. Samuel is the last judge of Israel. The people reject God and want a king. Saul is anointed as the first king, but he is not a good king. David, the shepherd boy is anointed and Saul is envious of him. David shows honor while Saul continues to self destruct.
🔥🔥🔥🔥🔥🔥🔥🔥🔥
إضغ بين إيديكم من أقوى الملازم التي صممتها
ملزمة تشريح الجهاز الهيكلي (نظري 3)
💀💀💀💀💀💀💀💀💀💀
تتميز هذهِ الملزمة بعِدة مُميزات :
1- مُترجمة ترجمة تُناسب جميع المستويات
2- تحتوي على 78 رسم توضيحي لكل كلمة موجودة بالملزمة (لكل كلمة !!!!)
#فهم_ماكو_درخ
3- دقة الكتابة والصور عالية جداً جداً جداً
4- هُنالك بعض المعلومات تم توضيحها بشكل تفصيلي جداً (تُعتبر لدى الطالب أو الطالبة بإنها معلومات مُبهمة ومع ذلك تم توضيح هذهِ المعلومات المُبهمة بشكل تفصيلي جداً
5- الملزمة تشرح نفسها ب نفسها بس تكلك تعال اقراني
6- تحتوي الملزمة في اول سلايد على خارطة تتضمن جميع تفرُعات معلومات الجهاز الهيكلي المذكورة في هذهِ الملزمة
واخيراً هذهِ الملزمة حلالٌ عليكم وإتمنى منكم إن تدعولي بالخير والصحة والعافية فقط
كل التوفيق زملائي وزميلاتي ، زميلكم محمد الذهبي 💊💊
🔥🔥🔥🔥🔥🔥🔥🔥🔥
This presentation was provided by Racquel Jemison, Ph.D., Christina MacLaughlin, Ph.D., and Paulomi Majumder. Ph.D., all of the American Chemical Society, for the second session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session Two: 'Expanding Pathways to Publishing Careers,' was held June 13, 2024.
How to Download & Install Module From the Odoo App Store in Odoo 17Celine George
Custom modules offer the flexibility to extend Odoo's capabilities, address unique requirements, and optimize workflows to align seamlessly with your organization's processes. By leveraging custom modules, businesses can unlock greater efficiency, productivity, and innovation, empowering them to stay competitive in today's dynamic market landscape. In this tutorial, we'll guide you step by step on how to easily download and install modules from the Odoo App Store.
THE SACRIFICE HOW PRO-PALESTINE PROTESTS STUDENTS ARE SACRIFICING TO CHANGE T...indexPub
The recent surge in pro-Palestine student activism has prompted significant responses from universities, ranging from negotiations and divestment commitments to increased transparency about investments in companies supporting the war on Gaza. This activism has led to the cessation of student encampments but also highlighted the substantial sacrifices made by students, including academic disruptions and personal risks. The primary drivers of these protests are poor university administration, lack of transparency, and inadequate communication between officials and students. This study examines the profound emotional, psychological, and professional impacts on students engaged in pro-Palestine protests, focusing on Generation Z's (Gen-Z) activism dynamics. This paper explores the significant sacrifices made by these students and even the professors supporting the pro-Palestine movement, with a focus on recent global movements. Through an in-depth analysis of printed and electronic media, the study examines the impacts of these sacrifices on the academic and personal lives of those involved. The paper highlights examples from various universities, demonstrating student activism's long-term and short-term effects, including disciplinary actions, social backlash, and career implications. The researchers also explore the broader implications of student sacrifices. The findings reveal that these sacrifices are driven by a profound commitment to justice and human rights, and are influenced by the increasing availability of information, peer interactions, and personal convictions. The study also discusses the broader implications of this activism, comparing it to historical precedents and assessing its potential to influence policy and public opinion. The emotional and psychological toll on student activists is significant, but their sense of purpose and community support mitigates some of these challenges. However, the researchers call for acknowledging the broader Impact of these sacrifices on the future global movement of FreePalestine.
1. 11
Identify the different types of solutionsIdentify the different types of solutions
Investigate experimentally the effect of structure andInvestigate experimentally the effect of structure and
temperature on solubility of solids in watertemperature on solubility of solids in water
Distinguish among solutions, suspensions and colloidsDistinguish among solutions, suspensions and colloids
Identify suitable separation techniques based onIdentify suitable separation techniques based on
difference in properties of the components ofdifference in properties of the components of
mixturesmixtures
Describe the extraction of sucrose from sugar caneDescribe the extraction of sucrose from sugar cane
Mixtures and Separations
Chapter 8
Learning Outcomes
2. Copper(II) sulphate
Pure substances
A pure substance is a single substance not
mixed with anything else.
Sugar and table salt are examples of pure
substances.
Pure substances usually exist in crystal form.
For example, table salt, sugar and copper(II)
sulphate all exist as crystals.
A pure substance can be an element or a
compound.
Sugar crystals
Chapter 8
Mixtures and Separations
3. Pure and impure substances
A pure substance has
a fixed melting point
and boiling point.
For example, pure
water boils at 100 o
C,
and melts at 0 o
C.
b.p. 100 o
C
m.p. 0 o
C
Chapter 8
Mixtures and Separations
4. Impure substances or mixtures
A mixture on the other hand, is an impure substance.
It does not have a fixed melting point and boiling point.
It melts or boils over a range of temperatures.
For example, sea water boils at about 102 o
C and
freezes at around – 2.5o
C.
In general, an impurity lowers the melting point and
increases the boiling point of a substance.
Chapter 8
Mixtures and Separations
5. Impure substances or mixtures
In nature, most substances are impure. They consist of
two or more substances mixed together.
Such substances are called mixtures.
Examples of mixtures are air, sea water, petroleum
and granite rock.
Mixtures can be purified or separated by physical
methods.
Chapter 8
Mixtures and Separations
6. 66
A MixtureA Mixture
Air is made up of different gases: nitrogen, oxygen, carbonAir is made up of different gases: nitrogen, oxygen, carbon
dioxide and noble gases such as argon, neon, and helium.dioxide and noble gases such as argon, neon, and helium.
The gases in air can be easily separated by liquefaction followedThe gases in air can be easily separated by liquefaction followed
by fractional distillation.by fractional distillation.
Air is an example of a mixture.Air is an example of a mixture.
A mixture is made up of two or more substances
not chemically combined together.
Mixtures and Separations
Chapter 8
7. 77
Composition of a mixtureComposition of a mixture
A mixture can be made up ofA mixture can be made up of two or moretwo or more
elementselements..
E.g. Brass is a mixture of copper andE.g. Brass is a mixture of copper and
zinc.zinc.
A mixture can be made up of two
or more elements or compounds.
E.g. Air is a mixture which contains
both elements and compounds.
Copper
atom
Zinc
atom
Air contains both elements and
compounds.
Chapter 8
Mixtures and Separations
Brass
Element
Compound
8. 88
3. Hold a magnet over the mixture of
iron filings and sulphur.
The iron filings are attracted by the magnet
and can be separated from the sulphur.
4. Heat the mixture of sulphur and iron
filings strongly in an evaporating dish.
Examine the substance formed carefully.
A black solid is formed. It does not look
like iron filings or sulphur.
Compound of iron and sulphur
Mixture of iron and sulphur
ExperimentExperiment
Chapter 8
Mixtures and Separations
9. 99
5. Hold a magnet over the black solid. What happens?
The black solid is not attracted by the magnet.
The iron can no longer be separated from the sulphur in the black
solid.
6. When iron filings and sulphur are heated,
a compound called iron(II) sulphide is formed.
The equation for the reaction is:
Fe(s) + S(s) FeS(s)
ExperimentExperiment
Chapter 8
Mixtures and Separations
10. Homogeneous mixtures
A solution is a homogeneous mixture.
Characteristics of solutions:
When left to stand, the solute and solvent do not separate.
Solutes are not visible (particle size ≤ 1 nm).
All parts of the solution have the same chemical
composition, chemical and physical properties.
Chapter 8
Mixtures and Separations
11. Homogeneous mixtures
Solubility of a solution refers to the amount of solute
that is able to dissolve in a given quantity of solvent at
a fixed temperature and pressure.
The rate of dissolving of a solute depends on:
Temperature (e.g. Solubility increases with temperature.)
Surface area of solute (e.g. Fine sugar dissolves faster than
rock sugar.)
Rate of agitation (e.g. Stirring the solution increases the rate
of dissolving.)
Chapter 8
Mixtures and Separations
12. Heterogeneous mixtures
Heterogeneous mixtures have non-uniform
compositions which can be mechanically separated.
Examples of heterogeneous mixtures are colloids and
suspensions.
Colloids include fog, smoke, shaving cream, milk,
blood, styrofoam, gelatin, and cheese.
Suspensions include muddy water, paint and chalk
powder suspended in water.
Chapter 8
Mixtures and Separations
13. 1313
Quick check 1Quick check 1
1.1. Explain why air is a mixture but waterExplain why air is a mixture but water
is a compound.is a compound.
2.2. (a), State two reasons why a mixture of iron(a), State two reasons why a mixture of iron
filings and sulphur before heating is a mixture.filings and sulphur before heating is a mixture.
(b) When the mixture of iron filings(b) When the mixture of iron filings
and sulphur is heated strongly,and sulphur is heated strongly,
state two reasons whystate two reasons why
the solid formed is athe solid formed is a
compound.compound.
3.3. State whether the following diagrams on theState whether the following diagrams on the
right represent elements, mixtures orright represent elements, mixtures or
compounds.compounds. Solution
Chapter 8
Mixtures and Separations
14. 1414
Solution to Quick check 1Solution to Quick check 1
1. Air is a mixture because it is made up of many gases such as oxygen,
nitrogen, etc. not chemically combined together. The gases in air can
be separated by physical means. Water is a compound because it is
made up of hydrogen and oxygen chemically joined together. We
cannot separate the gases in water by physical means.
2. (a) It is a mixture because the iron and sulphur can be separated by
physical means e.g. by using a magnet. Also, no heat or light is given
out when the iron filings and sulphur are mixed together.
(b) When the mixture of iron filings and sulphur is heated strongly, a
compound is formed because a chemical reaction occurs e.g. heat and
light are given off. Also, the sulphur and iron in the compound can no
longer be separated by physical means such as by using a magnet.
3. (a) compound, (b) compound, (c) mixture, (d) mixture
Return
Chapter 8
Mixtures and Separations
15. Methods of separating Mixtures
Filtration
Evaporation
Crystallisation
Sublimation
Simple distillation
Fractional distillation
Use of separating funnel
Chromatography
Chapter 8
Mixtures and Separations
16. Filtration
Filtration is the method used to separate an insoluble solid from a
liquid.
An example would be to separate a mixture of sand and water.
The liquid (water) that
has passed through
the filter paper is called
filtrate.
The solid (sand) left on the
filter paper is called residue.
Chapter 8
Mixtures and Separations
17. Evaporation
Evaporation is the method used to separate a solute from a solution.
It can only be used for solids which do not decompose under heat
e.g. table salt (sodium chloride).
It is done by heating the solution in an evaporating dish until it is
completely dry.
Crystals of salt remain after the solution is evaporated to dryness.
Chapter 8
Mixtures and Separations
18. Crystallisation
Crystallisation is the method used to obtain pure crystals from a solution.
It is done by heating the solution in an evaporating dish until it is saturated.
The hot solution is then allowed to cool.
Crystals will be formed on cooling. They are then dried between sheets of
filter paper.
Chapter 8
Mixtures and Separations
19. Sublimation
Sublimation is the method used to
separate a substance which
sublimes from a mixture.
Examples of substances which
sublime are: iodine, ammonium
salts, naphthalene and dry ice.
The mixture is heated in an
evaporating dish covered with
a filter funnel.
The substance which sublimes
will be changed into a vapour
and then formed back on the
inside of the funnel.
To separate ammonium chloride
from sodium chloride, this
method can be employed.
Chapter 8
Mixtures and Separations
20. Simple distillation
Distillation is the method used to
obtain a pure solvent from a
solution. E.g. pure water from
seawater.
It is done by heating the solution
in a distillation flask and collecting
the vapour that boils off.
A condenser is used to condense
the hot vapour and change it to a
liquid.
The condenser is cooled by the
flow of cold water (in the
condenser) from the tap. The pure liquid collected from
distillation is called distillate.
Chapter 8
Mixtures and Separations
21. Fractional distillation
Fractional distillation is used to
separate two or more miscible liquids
with different boiling points.
A fractionating column and a
condenser are used.
Example: Mixture of ethanol and water
When the thermometer reaches a
steady temperature of 78 o
C,
ethanol is collected.
Water is collected when the
thermometer reaches a steady
temperature of 100 o
C.
Chapter 8
Mixtures and Separations
Separation of ethanol-water mixture
by fractional distillation
22. Use of separating funnel
This method is used to separate a mixture
of immiscible liquids.
The mixture is placed into a separating
funnel and allowed to settle into two layers.
Example: Mixture of oil and water
The tap is first opened to allow the water to
drain out of the funnel.
After all the water has drained out, another
beaker is placed below the funnel and oil is
now drained out.
Separation of oil-water mixture
by using a separating funnel
Chapter 8
Mixtures and Separations
23. Chromatography
Chromatography is a method used to
separate and identify small quantities of
substances.
There are different kinds of
chromatography techniques, such as gas
chromatography, liquid chromatography
and paper chromatography.
It is based on the principle that
different substances have different
solubilities in the same solvent.
The more soluble substance will get
carried along faster by the solvent
and move further ahead than the
less soluble substances.
Chromatography can be used to
detect and identify very small
quantities of substances. It is used
to detect banned dyes used in
food colourings, and detect
illegal drugs used by athletes
during major competitions.
Paper Chromatography
Chapter 8
Mixtures and Separations
24. Setup for paper chromatography
-The starting line must be drawn in
pencil, not ink. This is because unlike
ink, pencil lead is insoluble in the
solvent and will not interfere with the
chromatogram.
-The spots of mixtures must be placed
above the solvent level, so that they
will not immediately dissolve in the
solvent, and the solvent has time to
slowly move up.
starting line
solvent
solvent front
chromatography
paper
large
beaker
glass cover
-The solvent front must be allowed to move as far up the paper as possible to
ensure that all the dyes are separated.
Chapter 8
Mixtures and Separations
25. The Rf value of a substance
Rf value = distance moved by a substance
distance moved by solvent front
(7 cm)
(10 cm)
E.g. Rf value of red dye = 7 cm = 0.7
10 cm
Sometimes the chromatogram needs to be sprayed with a locating
agent to make the colourless spots in the chromatogram appear.
Chapter 8
Mixtures and Separations
26. Paper chromatography
Worked example
The chromatogram shows 3 single dyes
red, green and blue, and also four
unknown samples P, Q, R and S.
Identify the dyes present in each of the
samples, P, Q, R, S.
Solution
Sample P contains green dye and one unknown dye.
Sample Q contains only blue dye.
Sample R contains green, blue and red dyes.
Sample S contains green and red dyes.
Chapter 8
Mixtures and Separations
27. 2727
Identify the various method separation methods used in the diagram below .
Chapter 8
Mixtures and Separations
28. Quick check
1. State the method you will use to
separate the following substances.
(a) calcium carbonate from table salt
(b) iodine from sodium chloride
(c) table salt from seawater
(d) sugar from sugar solution
(e) pure water from sewage water
(f) ethanol from beer
(g) yellow dye from durian ice cream
2. Explain the following in chromatography.
(a) Why is the starting line not drawn with ink or a ball point pen?
(b) The spots of samples on the start line should be small.
(c) What is the biggest advantage of chromatography?
3. A sample of ink was analysed using paper chromatography (see
diagram above). Identify the dyes present in the ink.
Solution
Chapter 8
Mixtures and Separations
29. Solution to Quick check
1. State the method you will use to separate the following substances.
(a) dissolution, followed by filtration
(b) sublimation
(c) evaporation
(d) crystallisation
(e) distillation
(f ) fractional distillation
(g) chromatography
2. Explain the following in chromatography.
(a) Ink contains dyes which could dissolve in the solvent and
interfere with the chromatogram.
(b) So that they would not smudge the paper.
(c) It can detect and identify very small amounts of substances.
3. Blue and yellow dyes
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Chapter 8
Mixtures and Separations