This document discusses several key concepts in chemistry including the following:
1. Everything in the universe is made of approximately 100 different types of atoms that combine to form all substances. Chemical reactions involving these atoms are important for life and cause many problems.
2. The scientific method is used by scientists to understand the universe through observation, hypothesis, experimentation, and developing theories. Theories can be modified over time with new evidence.
3. Matter can exist as elements, compounds, mixtures, gases, liquids, and solids. Various separation and classification methods are used to distinguish these forms of matter based on their physical and chemical properties.
1. Chemistry is the study of matter and its properties and changes. It impacts many areas including health, energy, materials, food and agriculture.
2. Matter can be classified as elements, compounds or mixtures. Elements cannot be broken down further, compounds are made of two or more elements chemically bonded together, and mixtures maintain their individual identities.
3. The three main states of matter are solids, liquids, and gases. Physical and chemical changes alter or do not alter the composition of matter. The scientific method is used to study chemistry through observation, hypothesis, experimentation and theory development.
Capítulos 1 y 2 del libro de química de changyesu90uy
This document provides an overview of the development of atomic theory and models of the atom. It discusses key discoveries and experiments including:
- Dalton's atomic theory from 1808 that proposed atoms as fundamental particles and that elements are composed of unique atoms.
- J.J. Thomson's discovery in 1906 that the cathode rays were composed of negatively charged particles (electrons) much lighter than atoms.
- Rutherford's gold foil experiment from 1911 that showed the positive charge and most of the mass of atoms are concentrated in a very small nucleus.
- Chadwick's discovery of the neutron in 1932, which has no charge and a mass similar to protons.
- The modern definitions of atomic number as
Chemistry is the study of matter, its properties, and the changes it undergoes. Matter is anything that has mass and takes up space, and is composed of atoms. Atoms are the building blocks of matter and each element is made of the same type of atom. Compounds are made of two or more different elements chemically bonded together. Mixtures contain two or more substances mixed but not chemically combined. Measurements in chemistry use significant figures and units to accurately quantify properties and changes in matter.
Chemistry is the study of matter, its properties, and the changes it undergoes. Matter is anything that has mass and takes up space, and is composed of atoms. Atoms are the building blocks of matter and each element is made of the same type of atom. Compounds are made of two or more different elements chemically bonded together. Mixtures contain two or more substances mixed but not chemically combined. Measurements in chemistry use significant figures and the SI system of units including meters, grams, and liters.
This document provides an overview of basic chemistry concepts. It discusses the following key points in 3 sentences or less:
- Chemistry is the study of matter and the changes it undergoes. Matter can exist in solid, liquid, or gas states. A substance has a definite composition while a mixture combines two or more substances.
- An element is a substance that cannot be broken down further, with over 100 known elements. Compounds are formed from chemical combinations of elements. Physical changes do not alter substance composition while chemical changes do.
- Measurements in chemistry rely on devices like rulers, balances, and thermometers. The standard metric units and prefixes like milli and kilo are used to quantify measurements, properties
This document provides an overview of chemistry concepts including:
- Chemistry is the study of matter and its properties, covering topics like health, energy, materials, food and more.
- Matter is anything that has mass and takes up space, and can exist as elements, compounds and mixtures.
- Chemical and physical changes alter substances in different ways. The document also introduces concepts such as states of matter, properties of matter, units of measurement, and dimensional analysis.
General Chemistry 1 Module. Discussion on the different properties of Matter. Models of atom and history. Different orbitals and spdf notation. Identification of Atomic Mass, Weights, and Abundances of Isotopes.
1. Chemistry is the study of matter and its properties and changes. It impacts many areas including health, energy, materials, food and agriculture.
2. Matter can be classified as elements, compounds or mixtures. Elements cannot be broken down further, compounds are made of two or more elements chemically bonded together, and mixtures maintain their individual identities.
3. The three main states of matter are solids, liquids, and gases. Physical and chemical changes alter or do not alter the composition of matter. The scientific method is used to study chemistry through observation, hypothesis, experimentation and theory development.
Capítulos 1 y 2 del libro de química de changyesu90uy
This document provides an overview of the development of atomic theory and models of the atom. It discusses key discoveries and experiments including:
- Dalton's atomic theory from 1808 that proposed atoms as fundamental particles and that elements are composed of unique atoms.
- J.J. Thomson's discovery in 1906 that the cathode rays were composed of negatively charged particles (electrons) much lighter than atoms.
- Rutherford's gold foil experiment from 1911 that showed the positive charge and most of the mass of atoms are concentrated in a very small nucleus.
- Chadwick's discovery of the neutron in 1932, which has no charge and a mass similar to protons.
- The modern definitions of atomic number as
Chemistry is the study of matter, its properties, and the changes it undergoes. Matter is anything that has mass and takes up space, and is composed of atoms. Atoms are the building blocks of matter and each element is made of the same type of atom. Compounds are made of two or more different elements chemically bonded together. Mixtures contain two or more substances mixed but not chemically combined. Measurements in chemistry use significant figures and units to accurately quantify properties and changes in matter.
Chemistry is the study of matter, its properties, and the changes it undergoes. Matter is anything that has mass and takes up space, and is composed of atoms. Atoms are the building blocks of matter and each element is made of the same type of atom. Compounds are made of two or more different elements chemically bonded together. Mixtures contain two or more substances mixed but not chemically combined. Measurements in chemistry use significant figures and the SI system of units including meters, grams, and liters.
This document provides an overview of basic chemistry concepts. It discusses the following key points in 3 sentences or less:
- Chemistry is the study of matter and the changes it undergoes. Matter can exist in solid, liquid, or gas states. A substance has a definite composition while a mixture combines two or more substances.
- An element is a substance that cannot be broken down further, with over 100 known elements. Compounds are formed from chemical combinations of elements. Physical changes do not alter substance composition while chemical changes do.
- Measurements in chemistry rely on devices like rulers, balances, and thermometers. The standard metric units and prefixes like milli and kilo are used to quantify measurements, properties
This document provides an overview of chemistry concepts including:
- Chemistry is the study of matter and its properties, covering topics like health, energy, materials, food and more.
- Matter is anything that has mass and takes up space, and can exist as elements, compounds and mixtures.
- Chemical and physical changes alter substances in different ways. The document also introduces concepts such as states of matter, properties of matter, units of measurement, and dimensional analysis.
General Chemistry 1 Module. Discussion on the different properties of Matter. Models of atom and history. Different orbitals and spdf notation. Identification of Atomic Mass, Weights, and Abundances of Isotopes.
This document provides an introduction to chemistry, including:
- Defining chemistry as the study of matter, its structure and properties, and how matter changes.
- Explaining that chemistry is involved in many everyday materials and has various career applications.
- Describing the basic units that make up all matter - atoms, elements, and compounds.
- Discussing properties of matter like physical and chemical properties, and physical and chemical changes.
- Introducing important concepts like the periodic table, the scientific method, and laboratory safety procedures and equipment.
This document provides an overview of chemistry including:
- Chemistry is the study of matter, its structure and properties, and how matter changes.
- There are many careers in fields like engineering, medicine, and more that involve chemistry.
- Matter is made up of elements, compounds, and mixtures. Properties include physical properties that can be observed without changing identity, and chemical properties involving changes to form new substances.
This document provides an overview of chemistry concepts including the main areas and types of chemistry. It discusses organic chemistry and its importance due to its relationship to living matter. Biochemistry is introduced as the study of chemical reactions in living organisms, focusing on carbohydrates, lipids, proteins, and nucleic acids. The document also covers units of measurement and conversions between systems, density, temperature scales, and the concept of significant figures in measurements.
This document provides an overview of key concepts in chemistry including:
- Matter is anything that has mass and occupies space. Common types of matter include elements, compounds, and mixtures.
- Energy is the ability to do work or transfer heat and exists in various forms like chemical, thermal, nuclear, and electrical.
- Chemical and physical properties can be used to describe matter. Chemical properties involve changes in composition while physical properties can be observed without composition changes.
- Important concepts in chemistry include the laws of conservation of mass and energy, the relationship between matter and energy described by Einstein's equation E=mc2, and endothermic and exothermic reactions. Measurements involve units, significant figures, and conversions between
Chemistry- JIB Topic 1 Matter and MeasurementSam Richard
This document provides an overview of key chemistry concepts including:
1. Chemistry deals with matter and changes in matter at the macroscopic and microscopic levels. The scientific problem solving process involves stating the problem, formulating a hypothesis, and testing it with experiments.
2. The three states of matter are solids, liquids, and gases which differ in their particle arrangements and ability to change shape or volume. Physical and chemical properties and changes also differ based on whether the chemical composition changes.
3. Common units and measurements in chemistry include the mole, SI units, scientific notation, uncertainty in measurements, and calculating percent error.
A physical change alters a substance without changing its chemical identity. During a physical change, no new substance is created and no new chemical bonds form. Examples of physical changes include phase changes like melting, freezing, and vaporization, as well as dissolving and mixing substances that do not undergo chemical reactions.
JEE Chemistry Sample ebook, which helps you to understand the chapter in easy way also downaload sample papers and previous year papers and practice to solve the question on time. Download at www.misostudy.com.
Chemistry : The Study of change chapter 1RestinaBemis2
This document provides an overview of chemistry and some key concepts in the field. It discusses how chemistry relates to areas like health, energy, materials and technology. It also defines important terms like elements, compounds, mixtures, and the three states of matter. Several examples are given to illustrate states of matter and other concepts. Measurement units and significant figures are explained. The scientific method and types of chemical changes are defined. Dimensional analysis is introduced as a method for solving problems involving unit conversions.
This document provides an overview of chemistry as a science and introduces some key concepts. It discusses how chemistry relates to important areas like health, energy, materials, food and agriculture. The document then defines some basic chemistry terms including matter, elements, compounds, mixtures, physical and chemical changes, states of matter, properties of matter and units of measurement. It also introduces scientific notation and significant figures as well as methods for calculations.
New chm-151-unit-1-20powerpoints-20sp13s-140227172225-phpapp01Cleophas Rwemera
This document outlines key concepts for a chemistry course, including:
- The goals of identifying elements, understanding measurement units, significant figures, and types of errors.
- Definitions of matter, properties, physical and chemical changes, and the three states of matter.
- The International System of Units (SI) including common units like meters, grams, kelvin, and moles.
- Concepts like energy, elements, and the periodic table, and examples of calculating density, conversions between units, and solving chemistry problems systematically.
This document provides an overview of chemistry concepts including:
1. Chemistry is the study of matter and the changes it undergoes. The scientific method uses a systematic approach involving hypotheses, experiments, and analysis.
2. Matter can exist as elements, compounds, mixtures, and in three main states - solids, liquids, and gases. Chemical and physical changes alter substances in different ways.
3. The study of chemistry incorporates macroscopic observations and measurements as well as analysis at the microscopic level of atoms and molecules. Significant figures, units, and mathematical representations are important tools in chemistry.
This document discusses several concepts in chemistry that involve the use of math, including gas laws, molarity, scientific notation, units of measure, density, dimensional analysis, and specific heat. It provides examples of calculating density, using scientific notation to write very large and small numbers, and employing dimensional analysis to determine the number of atoms in a sample. Mathematics is an essential tool for understanding key chemical concepts.
The metric system evolved into the International System of Units (SI Units) which was adopted in 1960. The key features of the SI are decimalization, prefixes for units, and base units defined by physical constants like the speed of light. The English system is still used in the US but has been replaced in most other places by the SI.
This document provides an overview of basic chemistry concepts. It defines chemistry as the study of matter and its properties. The main branches of chemistry are described as organic, inorganic, physical, industrial, analytical, biochemistry, and nuclear chemistry. Matter is classified as pure substances or mixtures based on its composition. Elements are the basic units that make up all matter and can exist as atoms or molecules. Chemical properties and reactions are governed by laws such as the law of conservation of mass. The mole concept is introduced as a unit used to quantify the amount of substance.
This document provides an introduction to matter and its basic properties of mass and occupying space. It then outlines the table of contents for the rest of the document, which includes topics like units of measurement, mixtures, and separation techniques. The document discusses the SI system of units and provides examples of unit conversions. It also addresses concepts like uncertainty in measurement, types of mixtures (homogeneous and heterogeneous), and common separation methods like distillation and filtration.
This document provides an overview of key concepts in the unit on matter, including:
1. It defines matter as anything that has mass and volume, and discusses the states of matter (solid, liquid, gas, plasma), physical and chemical properties, and physical and chemical changes.
2. It explains the difference between elements, compounds, atoms, and molecules, and discusses measurement units and dimensional analysis.
3. It covers concepts like specific heat, calorimetry, phase change diagrams, and Archimedes' principle for determining density.
This document provides an overview of key concepts in introductory chemistry. It discusses three perspectives for understanding chemical systems: macroscopic, microscopic, and symbolic. It also covers the scientific method, properties of matter, phases of matter, chemical vs physical changes, the particulate nature of matter, and the use of measurements, units, and significant figures in chemistry. Example problems are provided to illustrate concepts like ratios, conceptual understanding of particles, and visualizing phenomena at different levels.
Basic concepts of chemistry class 8, 9, 10Supratim Das
Chemquest was established at Durgapur way back in 2003 by SUPRATIM DAS with specific objective to provide best Chemistry coaching to students of class XI-XII for preparation of competitive entrance exams. In last 17 years the institute has grown with hundreds of students joining TOP IIT/NIT/ Engineering and Medical Colleges every year and Chemquest has become a brand now in Durgapur widely acknowledge by parents and students.
Contact us:
Mobile Number: +919434008713
Whatsapp Number: +919434008713
Email: sdas.durgapur@gmail.com
Visit chemquest.co.in for more details.
Reimagining Your Library Space: How to Increase the Vibes in Your Library No ...Diana Rendina
Librarians are leading the way in creating future-ready citizens – now we need to update our spaces to match. In this session, attendees will get inspiration for transforming their library spaces. You’ll learn how to survey students and patrons, create a focus group, and use design thinking to brainstorm ideas for your space. We’ll discuss budget friendly ways to change your space as well as how to find funding. No matter where you’re at, you’ll find ideas for reimagining your space in this session.
This document provides an introduction to chemistry, including:
- Defining chemistry as the study of matter, its structure and properties, and how matter changes.
- Explaining that chemistry is involved in many everyday materials and has various career applications.
- Describing the basic units that make up all matter - atoms, elements, and compounds.
- Discussing properties of matter like physical and chemical properties, and physical and chemical changes.
- Introducing important concepts like the periodic table, the scientific method, and laboratory safety procedures and equipment.
This document provides an overview of chemistry including:
- Chemistry is the study of matter, its structure and properties, and how matter changes.
- There are many careers in fields like engineering, medicine, and more that involve chemistry.
- Matter is made up of elements, compounds, and mixtures. Properties include physical properties that can be observed without changing identity, and chemical properties involving changes to form new substances.
This document provides an overview of chemistry concepts including the main areas and types of chemistry. It discusses organic chemistry and its importance due to its relationship to living matter. Biochemistry is introduced as the study of chemical reactions in living organisms, focusing on carbohydrates, lipids, proteins, and nucleic acids. The document also covers units of measurement and conversions between systems, density, temperature scales, and the concept of significant figures in measurements.
This document provides an overview of key concepts in chemistry including:
- Matter is anything that has mass and occupies space. Common types of matter include elements, compounds, and mixtures.
- Energy is the ability to do work or transfer heat and exists in various forms like chemical, thermal, nuclear, and electrical.
- Chemical and physical properties can be used to describe matter. Chemical properties involve changes in composition while physical properties can be observed without composition changes.
- Important concepts in chemistry include the laws of conservation of mass and energy, the relationship between matter and energy described by Einstein's equation E=mc2, and endothermic and exothermic reactions. Measurements involve units, significant figures, and conversions between
Chemistry- JIB Topic 1 Matter and MeasurementSam Richard
This document provides an overview of key chemistry concepts including:
1. Chemistry deals with matter and changes in matter at the macroscopic and microscopic levels. The scientific problem solving process involves stating the problem, formulating a hypothesis, and testing it with experiments.
2. The three states of matter are solids, liquids, and gases which differ in their particle arrangements and ability to change shape or volume. Physical and chemical properties and changes also differ based on whether the chemical composition changes.
3. Common units and measurements in chemistry include the mole, SI units, scientific notation, uncertainty in measurements, and calculating percent error.
A physical change alters a substance without changing its chemical identity. During a physical change, no new substance is created and no new chemical bonds form. Examples of physical changes include phase changes like melting, freezing, and vaporization, as well as dissolving and mixing substances that do not undergo chemical reactions.
JEE Chemistry Sample ebook, which helps you to understand the chapter in easy way also downaload sample papers and previous year papers and practice to solve the question on time. Download at www.misostudy.com.
Chemistry : The Study of change chapter 1RestinaBemis2
This document provides an overview of chemistry and some key concepts in the field. It discusses how chemistry relates to areas like health, energy, materials and technology. It also defines important terms like elements, compounds, mixtures, and the three states of matter. Several examples are given to illustrate states of matter and other concepts. Measurement units and significant figures are explained. The scientific method and types of chemical changes are defined. Dimensional analysis is introduced as a method for solving problems involving unit conversions.
This document provides an overview of chemistry as a science and introduces some key concepts. It discusses how chemistry relates to important areas like health, energy, materials, food and agriculture. The document then defines some basic chemistry terms including matter, elements, compounds, mixtures, physical and chemical changes, states of matter, properties of matter and units of measurement. It also introduces scientific notation and significant figures as well as methods for calculations.
New chm-151-unit-1-20powerpoints-20sp13s-140227172225-phpapp01Cleophas Rwemera
This document outlines key concepts for a chemistry course, including:
- The goals of identifying elements, understanding measurement units, significant figures, and types of errors.
- Definitions of matter, properties, physical and chemical changes, and the three states of matter.
- The International System of Units (SI) including common units like meters, grams, kelvin, and moles.
- Concepts like energy, elements, and the periodic table, and examples of calculating density, conversions between units, and solving chemistry problems systematically.
This document provides an overview of chemistry concepts including:
1. Chemistry is the study of matter and the changes it undergoes. The scientific method uses a systematic approach involving hypotheses, experiments, and analysis.
2. Matter can exist as elements, compounds, mixtures, and in three main states - solids, liquids, and gases. Chemical and physical changes alter substances in different ways.
3. The study of chemistry incorporates macroscopic observations and measurements as well as analysis at the microscopic level of atoms and molecules. Significant figures, units, and mathematical representations are important tools in chemistry.
This document discusses several concepts in chemistry that involve the use of math, including gas laws, molarity, scientific notation, units of measure, density, dimensional analysis, and specific heat. It provides examples of calculating density, using scientific notation to write very large and small numbers, and employing dimensional analysis to determine the number of atoms in a sample. Mathematics is an essential tool for understanding key chemical concepts.
The metric system evolved into the International System of Units (SI Units) which was adopted in 1960. The key features of the SI are decimalization, prefixes for units, and base units defined by physical constants like the speed of light. The English system is still used in the US but has been replaced in most other places by the SI.
This document provides an overview of basic chemistry concepts. It defines chemistry as the study of matter and its properties. The main branches of chemistry are described as organic, inorganic, physical, industrial, analytical, biochemistry, and nuclear chemistry. Matter is classified as pure substances or mixtures based on its composition. Elements are the basic units that make up all matter and can exist as atoms or molecules. Chemical properties and reactions are governed by laws such as the law of conservation of mass. The mole concept is introduced as a unit used to quantify the amount of substance.
This document provides an introduction to matter and its basic properties of mass and occupying space. It then outlines the table of contents for the rest of the document, which includes topics like units of measurement, mixtures, and separation techniques. The document discusses the SI system of units and provides examples of unit conversions. It also addresses concepts like uncertainty in measurement, types of mixtures (homogeneous and heterogeneous), and common separation methods like distillation and filtration.
This document provides an overview of key concepts in the unit on matter, including:
1. It defines matter as anything that has mass and volume, and discusses the states of matter (solid, liquid, gas, plasma), physical and chemical properties, and physical and chemical changes.
2. It explains the difference between elements, compounds, atoms, and molecules, and discusses measurement units and dimensional analysis.
3. It covers concepts like specific heat, calorimetry, phase change diagrams, and Archimedes' principle for determining density.
This document provides an overview of key concepts in introductory chemistry. It discusses three perspectives for understanding chemical systems: macroscopic, microscopic, and symbolic. It also covers the scientific method, properties of matter, phases of matter, chemical vs physical changes, the particulate nature of matter, and the use of measurements, units, and significant figures in chemistry. Example problems are provided to illustrate concepts like ratios, conceptual understanding of particles, and visualizing phenomena at different levels.
Basic concepts of chemistry class 8, 9, 10Supratim Das
Chemquest was established at Durgapur way back in 2003 by SUPRATIM DAS with specific objective to provide best Chemistry coaching to students of class XI-XII for preparation of competitive entrance exams. In last 17 years the institute has grown with hundreds of students joining TOP IIT/NIT/ Engineering and Medical Colleges every year and Chemquest has become a brand now in Durgapur widely acknowledge by parents and students.
Contact us:
Mobile Number: +919434008713
Whatsapp Number: +919434008713
Email: sdas.durgapur@gmail.com
Visit chemquest.co.in for more details.
Reimagining Your Library Space: How to Increase the Vibes in Your Library No ...Diana Rendina
Librarians are leading the way in creating future-ready citizens – now we need to update our spaces to match. In this session, attendees will get inspiration for transforming their library spaces. You’ll learn how to survey students and patrons, create a focus group, and use design thinking to brainstorm ideas for your space. We’ll discuss budget friendly ways to change your space as well as how to find funding. No matter where you’re at, you’ll find ideas for reimagining your space in this session.
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
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it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
Leveraging Generative AI to Drive Nonprofit InnovationTechSoup
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This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
CH1.pdf
1. 1
Chapter 1
Chemistry: The Central Science
Introduction and Some Basic
Concepts
General Chemistry 2020 – 2021
16
2. 2
Everything in this universe is made out of approximately
100 different kinds of atoms.
Sand (Silicon, Oxygen)
Table Salt (Sodium, Chloride)
Water (Oxygen, Hydrogen)
They are as letters in an alphabet.
Chapter1
Why Chemistry?
4. 4
Chemical reactions are very common in this life
and are important for our survival on the Earth.
They also cause many problems for humanity!
Can you think of “good” and “bad” chemical
reactions?
Why Chemistry?
5. 5
Scientific Method
The scientific method is the way used
by scientists to understand the universe
and its changes.
The more creative you’re at solving
problems, the more effective you will be
in your career and your personal life.
Chemistry helps to develop
solving problems capabilities.
6. 6
Steps of scientific methods:
Observation.
• Can be qualitative or quantitative.
Prediction (Hypothesis).
• Trying to explain the observation.
Experiment.
• Performed to test the validity of the hypothesis.
• Experiments always produce new information.
Scientific Method
To understand the universe and its
changes.
7. 7
Scientific Method
A set of valid hypotheses is
assembled into a theory (model).
This theory is confirmed, modified
or may be discarded as more
observations are recorded. Thus,
it is a continuous process.
8. 8
Theory vs. Law
Theory changes over time as more
observations from experiments are recorded.
Some observations are found to apply to
many different systems.
Law (what happens)
A summary of observed behaviors applied to
different systems.
Law of conservation of mass.
Law of conservation of energy.
Theory (why it happens)
An attempt to explain these observations.
10. 10
Classification of Matter
Matter ()المادة is anything occupying the space
and having a mass.
Matter anything that has mass and volume (or
occupies space)
Matter can be:
A substance is a form of matter that has a
defined composition and unique properties.
A mixture is a combination of two or more
substances that retain their distinct identities.
11. 11
Classification of Matter
States of matter:
Solid: rigid, has fixed volume and shape.
Liquid: has definite volume but not fixed shape.
Gas: has no fixed volume or shape. and is compressible.
12. 12
Classification of Matter
Chapter 1 Section 2
• Wood
• Sand
• Rocks
• Gasoline
• Juices and tea
• Air (N2, O2, H2,
CO2, etc.)
• H2O
• NaCl
• H2SO4
• C (carbon)
• Hg (mercury)
• H or H2
(hydrogen)
13. 13
Separation (Physical) Methods
Based on the physical properties of the substances
(boiling point, adsorption, solubility, etc.)
Separation methods discussed in the text:
Distillation.
Filtration.
Chromatography.
Chapter 1 Section 2
14. 14
Atoms, Elements and Compounds
Chemical changes (decomposition of compounds or recombining elements),
such as electrolysis, heating, and photolysis.
Compounds (
المركبات
) are substances with
constant composition that can be broken
down into elements by chemical processes.
Compound – substance made of 2 or more
types of atoms that are chemically bonded.
Elements (
العناصر
) are substances that can’t
be decomposed into simpler substances by
physical or chemical means
Element – pure substance made of only
one type of atom.
Atom()الذرة- smallest unit of an element
that keeps the properties of element.
15. 15
Molecule and Mixture
Molecule()الجزيء: type of compound in which the bonds are covalent
bonds.
Mixture ()الخليط
•In chemistry, a mixture is a material made up of two or more different
substances which are mixed.
A mixture differs from a compound in that( في المركب عن الخليط )يختلف
(
1
) mixed in any proportion (نسبة باي )يخلط
(
2
.) the components of which can be separated ) اهلصف
( by simple mechanical
means.
• Separating the Components of a Mixture: techniques to separate the
components of mixtures (Size, density, solubility, electrical charge
16. 16
Classification of Matter
Classify the following as mixtures, elements,
compounds, etc.
Aluminum foil:
substance, element
Table salt:
substance, compound
Milk:
mixture, homogeneous
Sea water:
mixture, homogeneous
Copper wire:
substance, element
17. 17
The Properties of Matter
Quantitative: expressed using numbers.
Qualitative: expressed using properties.
Physical properties: can be observed and measured
without changing the substance.
Examples: color, melting point, states of matter.
Physical changes: the identity of the substance stays
the same and only its state changes.
Examples: changes of state (melting, freezing).
18. 18
The Properties of Matter
Chemical properties: must be determined by the
chemical changes that are observed.
Examples: flammability, acidity, corrosiveness, reactivity.
Chemical changes: after a chemical change, the
original substance no longer exists
Examples: combustion, digestion, corrosion.
20. 20
The Properties of Matter
Extensive
property: depends
on the amount of
matter.
Examples: mass,
length.
Intensive
property: does not
depend on the
amount of matter.
Examples: density,
temperature, color.
Mass of water 100.0 g 10.0 g
Volume of water 0.100 L 0.010 L
Temperature of water 25 °C 25 °C
Density of water 1.00 g/mL 1.00 g/mL
22. 22
Scientific Measurement
Number Unit
(1) Metric Units
International System (SI Units)
(2) English Units
Used in Science
There are two major systems of measurements:
Making observations can be done quantitatively or qualitatively.
A quantitative observation is called a measurement. It must
include two important pieces of information:
23. 23
Units of Measurement
Number Unit
10 kilometers
1 gram
5 kelvin
20 miles
1 pound
60 Fahrenheit
(1) Metric
Units
International
System (SI
Units)
(2) English
Units
Used in
Science
There are two
major systems of
measurements:
24. 24
The Fundamental SI Units
All other units of measurement can be derived from the above
seven fundamental SI units .
25. 25
Using Prefixes in the SI System
The distance between Sanaa and
Ibb is 90,000 meters.
90×103 meters.
90 kilo-meters (km)
The capacity of this computer is
80,000,000,000 bites.
80×109 bites
80 giga-bites (GB)
27. 27
Scientific Notation
0.0001 kg
1×10-4 kg
0.1 g
1 with 35 zeros kg
1×1035 kg
Mass vs. Weight
How much does that pin weigh?
How much does the earth weigh?
Scientific Notation
28. 28
Scientific Notations
123.1 = 1.231× 102 = 1.231 × 100
0.00013 = 1.3 × 10-4 = 1.3 / 10000
= 0.13 × 10-3
Avogadro’s Number*:
602,214,000,000,000,000,000,000
*The number of atoms contained in 12 g of carbon and is equal to 1 mole.
6.022 × 1023
Scientific notation is a very convenient way to express the number of atoms
in chemistry problems.
29. 29
Temperature
Three systems are used to measure temperatures:
Celsius scale (°C)
Kelvin scale (K)
Fahrenheit (°F)
You have to be able to convert from one scale to
another.
30. 30
The Three Major Temperature Scales
Fahrenheit (F) Celsius (oC) Kelvin (K)
31. 31
Celsius Scale vs. Kelvin Scale
Temperature scales for °C
and K are identical, but
their zeros are different.
TK = TC + 273.15
TC = TK – 273.15
32. 32
Fahrenheit Scale vs. Celsius Scale
Both unit temperature
size and zero locations
are different.
Since:
180°F = 100°C => 9°F =
5°C
and:
32°F = 0°C
Then to convert from °F to °C:
[Tf (°F) – 32 (°F)] = Tc
(°C)
5°C
9°F
33. 33
Fahrenheit Scale vs. Celsius Scale
[ Tc (a) – Tc (b) ] °C = (5°C/9°F) [ Tf (a) – Tf (b) ] °F
When Tc (b) = - 40°C, then Tf (b) = -40°F
giving that:
[ Tc (a) – (-40) ] °C = (5°C/9°F) [ Tf (a) – (-40) ] °F
Thus:
or
F
9
C
5
40
40
f
c
T
T
C
5
F
9
40
40
c
f
T
T
34. 34
Volume
Volume is not an SI unit, but it is
extremely important in chemical
measurements.
Volume = 1m × 1m × 1m = 1m3
1m = 10dm
(1m)3 = (10dm)3
1m3 = 1000dm3
1dm3 = 1L
1L = 1000mL = 1000cm3
1mL = 1cm3
(milli)Liter milli = 10-3
(centi)Meter centi = 10-2
36. 36
Density
It is the mass of substance
per unit volume. volume
mass
Density
Substance Physical State Density (g/cm3)
Oxygen Gas 0.00133
Hydrogen Gas 0.000084
Ethanol Liquid 0.789
Water Liquid 0.998
Aluminum Solid 1.47
Iron Solid 7.87
Mercury Liquid 13.6
37. 37
Uncertainty in Measurement
A measurement always has
some degree of uncertainty.
Chapter 1 Section 5
20.16 ml
20.17 ml
20.15 ml
20.18 ml
20.16 ml
certain
digit
uncertain digit
(must be estimated)
• Uncertainty is
± 0.01 ml.
• Certain and
uncertain digits are
known as significant
figures.
38. 38
Now you should be able to tell how many
digits you need to include in your reading
(measurement).
20 ml
20.1 ml
20.16 ml
20.160 ml
20.1600 ml
Uncertainty in Measurement
Chapter 1 Section 5
Which one??
These meaningful digits are the significant figures
39. 39
Uncertainty in Measurement
Different equipments have different
uncertainties in their measurements.
Chapter 1 Section 5
2.5 ± 0.1 cm
2.46 ± 0.01 cm
These meaningful
digits are the
significant figures
Uncertainty
40. 40
Significant Figures (المعنوية )األرقام
In many cases, important physical quantities are obtained
from measured values.
Volume = l w h
Density = mass / volume
Calculations need to be done on the basis of Significant
Figure (S.F.) Rules
Rules for counting S.F.
Rules of mathematical operations on S.F.
Implication of the word “Significant”. It is to have the
correct degree of uncertainty in the resultant physical
quantities.
Mathematical
operations
41. 41
Rules for Counting Significant Figures
1- Nonzero integers are always counted as
S.F.
Example: Give the number of S.F. for the following:
34
236
17296.1
12.1×102 Exponential (Scientific) notation
Chapter 1 Section 5
42. 42
Rules for Counting Significant Figures
2- Zeros (leading zeros, captive zeros, and
trailing zeros)
a) Leading zeros are not counted as S.F.
Example: Give the number of S.F. for the following:
00121.1
0.0025
Chapter 1 Section 5
43. 43
Rules for Counting Significant Figures
b) Captive zeros are always counted as S.F.
Example: Give the number of S.F. for the following:
1.008
701.1 ×10-4
3.000000008
0.0901
Chapter 1 Section 5
44. 44
Rules for Counting Significant Figures
c) Trailing zeros are counted as S.F. only if the
number contains a decimal point.
Example: Give the number of S.F. for the following:
1.000
320.00 ×10-1
100 (can’t tell!) may be 1, 2 or 3.
100.
100.0
Chapter 1 Section 5
45. 45
Rules for Counting Significant Figures
3- Exact numbers are assumed to have an
infinite number of S.F.
Examples:
3 Apples is 3.00000000 (zeros are all the way to ∞)
2 in 2πr (the circumference of a cycle).
1 km = 1000 m
1 in = 2.54 cm
Chapter 1 Section 5
Mathematical
relationships
Definitions
46. 46
Exercise
How many significant figures are there in the
following numbers?
Chapter 1 Section 5
3004
5.
10
10
120
0
.
0
250.
m
cm3
kg
47. 47
Mathematical Operations
Multiplication or division
4.56 × 1.4 = 6.38 6.4
Chapter 1 Section 5
From
calculator
before
correction
Number
of S.F. 3 2 2 S.F. (After
correction)
Addition and Subtraction
12.11
+ 18.0
+ 1.013 31.1
31.123
before
correction
3 S.F. (After
correction)
48. 48
Rule for Rounding Numbers (االرقام تقريب )قواعد
6.38
The digit to be removed
If ≥ 5, then round up, i.e. the 3 becomes 4.
6.4
If < 5, then the digit stays unchanged.
6.34 becomes 6.3
49. 49
Exercises
Perform the following mathematical operation and
express the result to the correct number of significant
figures:
Chapter 1 Section 5
01
1
273
0821
0
102
0
.
.
.
Rounding off should be carried out for the final answer
and NOT to the intermediate answers. However, you must
keep track of the significant figures in the intermediate
steps.
50. 50
Precision and Accuracy
Chapter 1 Section 5
Random error Systematic error
Precise but not
accurate
“reproducible”
Neither precise
nor accurate
Accurate and
precise
Poor technique Good technique but
needs calibration
Good technique
51. 51
Precision and Accuracy
Accuracy: Agreement of a particular value
(measurement) with the true value.
Precision: Agreement among several
values (measurements), not necessarily
agreeing with the true value.
Chapter 1 Section 5
52. 52
Precision and Accuracy
Chapter 1 Section 5
Student A Student B Student C
0.335 g 0.357 g 0.369 g
0.331 g 0.375 g 0.373 g
0.333 g 0.338 g 0.371 g
Average:
0.333 g 0.357 g 0.371 g
True mass was 0.370 grams
Three students are asked to determine the
mass of an aspirin tablet.
53. 53
Precision and Accuracy
Chapter 1 Section 5
Three students are asked to determine the
mass of an aspirin tablet.
True mass was 0.370 grams
54. 54
Conversion Factors
Used to convert from one unit to another.
Chapter 1 Section 6
Example 1:
How many centimeters in
25.5 inches (in)?
in
1
cm
2.54
in
25.5 64.8 cm
Example 2:
How many inches in 25.5
centimeters?
cm
2.54
in
1
cm
25.5 10.0 in
55. 55
Dimensional Analysis – Tracking Units
1L = 1000 ml
1 ml = 0.001 L
= 1× 10-3 L
Chapter 1 Section 6
Example 3:
How many ml are in
1.63 L?
Which direction you choose?
1.63 L × =
1.63 L × =
1 L
1000 ml
?
1 L
1000 ml
L2
ml
0.00163
1.63×103 ml
56. 56
How many centimeters are in 0.25 megameters?
0.25 megameters × = 0.25×106 m
0.25×106 m × = 0.25×108 cm
= 2.5×107 cm
= 25.×106 cm
Solving Problems Using Dimensional
Analysis
Chapter 1 Section 6
megameters
1
m
1×106
1 meters
cm
100
57. 57
The Food and Drug Administration (FDA) recommends
that dietary sodium intake be no more than 2400 mg
per day.
What is this mass in pounds (lb), if 1 lb = 453.6 g?
Solving Problems Using Dimensional
Analysis
Chapter 1 Section 6
lb
10
5.3
g
453.6
lb
1
mg
1000
g
1
mg
2400 3
58. 58
Exercise
Perform the following mathematical operation and
express the result to the correct number of significant
figures:
4326
.
0
705
.
80
623
.
0
470
.
0
1
.
3
526
.
2
Rounding off should be carried out for the final answer
and NOT to the intermediate answers. However, you must
keep track of the significant figures in the intermediate
steps.
59. 59
Exercise
Methodology to solve such problems:
• Start with the quantity given in the question.
• Use possible conversion factors to convert the unit of the
given quantity in the question to the desired/needed unit.