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Dacota_blue K12: Science 7: Quarter 1: Module 1 matter
This document discusses solutions and related concepts. It begins by defining matter and the different states of matter. It then discusses solutions in depth, including the components of solutions, different types of solutions, factors that affect solubility rates, and ways to express concentration. Examples are provided throughout to illustrate these concepts. Concentration is discussed further, including percentage by weight and by volume. Factors that affect how quickly solutes dissolve are also outlined.
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Dacota_blue K12: Science 7: Quarter 1: Module 1 matter
- 1. SPG K AP I T M U STRIKTONG PAKIKINIG SA GURO Ang Kinakailangan
- 2. Diversity of Materialsin the Environment Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.” -Albert Einstein
- 3. REVIEW WHAT ISMATTER?
- 4. What is matter? MATTER is anything that takes up space and has a mass. MATTER is composed of tiny particles called atoms.
- 5.
- 6. STATE OF MATTER 1: Solid 2: Liquid 3: Gas 4: Plasma
- 7. STATE OF MATTER 1: Solid 2: Liquid 3: Gas : Plasma
- 8. PHYSICAL STATE OFMATTER SOLIDS:
- 9. PHYSICAL STATE OFMATTER LIQUID:
- 10. PHYSICAL STATE OFMATTER GAS:
- 11. PHYSICAL STATE OFMATTER PLASMA:
- 12. CHANGES IN STATEOF MATTER
- 13. CHANGES IN STATEOF MATTER(The Water Cycle)
- 14.
- 15. Overview In Grade6, you have learned about different mixtures and their characteristics. different mixtures and their characteristics. mixing a solid and a liquid or combined two different liquids. homogeneous or heterogeneous mixtures
- 16. Overview Homogeneous mixturesare called solutions.
- 17. •Nature of solute •Nature of solvent •Temperature •Pressure •Dilute or concentrated •Unsaturated, saturated, or supersaturated •% weight •% volume % weight /volume •CONDUCTIVITY •COLLIGATIVE PROPERTIES
- 18.
- 20. First things first… You observed in Activity 1 that a solution is not always a liquid; it can be solid, liquid, or gas. In addition, solutions may either be found in nature or are manufactured. • Solutions are homogeneous mixtures made up of molecules or ions. • Composed of solute and solvent. • A solution does not always have to be liquid, it can be solid or gaseous.
- 21. In Activity 2,you found out that a solution is formed when a solute dissolves in a solvent to form a single phase that appears uniform throughout. A solution is clear. In a solution, the particles are too small that they cannot be seen by the unaided eye. The particles in solution are smaller than the pores of the filter paper or the cheesecloth and so these can pass through the filter. ACTIVITY 2 What are the Properties of Solutions?
- 22. TYPES OF SOLUTION LEARNING COMPETENCY: The learner investigates the different types of solutions.
- 23. Types of Solution Type (Phase) Solute Solvent Example Gaseous Gas Gas air, water vapor in air Liquid Gas Liquid Softdrinks Liquid Liquid vinegar, alcohol
- 24. Types of Solution Type (Phase) Solute Solvent Example Liquid solid liquid seawater, brine Solid gas solid charcoal filter liquid solid dental amalgam (Hg and other metal except Fe)
- 25. Types of Solution Solid solid solid steel (Fe and C), bronze(Cu and Sn), brass (Cu and Zn) Type (Phase) Solute Solvent Example
- 26. Types of Solution:GASEOUS SOLUTION Solute: Gas Solvent: Gas
- 27. Types of Solution:LIQUID SOLUTION Solute: Gas Solvent: Liquid
- 28. Types of Solution:LIQUID SOLUTION Solute: Liquid Solvent: Liquid
- 29. Types of Solution:LIQUID SOLUTION Solute: Solid Solvent: Liquid
- 30. Types of Solution:SOLID SOLUTION Solute: Gas Solvent: Solid
- 31. Types of Solution:SOLID SOLUTION Solute: Liquid Solvent: Solid
- 32. Types of Solution:SOLID SOLUTION Solute: Solid Solvent: Solid
- 33.
- 34.
- 35. ALLOYS are solid(metal) solutions.
- 36. Water as theUniversal SOLVENT Aqueous solution-A solution in which the solvent is water.
- 37. Naturally Occurring Solutions Examples of solutions that occur naturally are natural bodies of water like the seas and ocean, blood plasma, air, and some mineral ores.
- 38. Manufactured/Processed Solutions Almostevery household uses vinegar for cooking and cleaning purposes. Vinegar usually contains about 5% acetic acid in water. Some vinegar are clear homogeneous mixtures (solutions). Other kinds of vinegar are colloidal.
- 39. In Activity 3,you will find out how much solute can dissolve in a given amount of solvent and find out the type of solution based on whether there is excess solute or not. At higher grade levels, you will learn more of the detailed processes that happen when a solute dissolves in a solvent. ACTIVITY 3 What is the Evidence that a Solution is Saturated?
- 40. In Activity 3,you have observed that there is a maximum amount of solute that can dissolve in a given amount of solvent at a certain temperature. This is what is called the “solubility” of the solute. From your everyday experience, you also observe that there is a limit to the amount of sugar you can dissolve in a given amount of water.
- 41. The solubilityof some solutes decreases as temperature increases. On the other hand, there are solutes that increase their solubility at higher temperatures. For some other solutes, their solubility is not affected by an increase in temperature. Since the effect of temperature on different solutes is more accurately explained using solubility curves,
- 42. SATURATION ***Learning Competency:investigates the different types of solutions. - unsaturated - saturated - supersaturated
- 43. SATURATION Saturated Unsaturated Supersaturated My brain really hurts! I can’t take it anymore… Stress week! huhuhu During the addition of solid solute into a liquid solvent, a condition is reached where no more solute dissolves. The excess solid simply lies undissolved at the bottom.
- 44.
- 45. Saturated Solution Thesolution that contains the maximum amount of solvent at a constant Temperature and Pressure is called “Saturated” solution.
- 46. Unsaturated Solution Theamount of dissolved solute is less than the maximum the solvent can dissolved.
- 47. Unsaturated Solution Asolution that contains less solute than a saturated solution at a given temperature and pressure.
- 48. Supersaturated Solution Whena saturated solution together with the undissolved solid is heated then cooled, some of the excess solute will crystallized.
- 49. Supersaturated Solution Asolution that contains more solute than it can theoretically hold at a given temperature; excess solute precipitates if a seed crystals is added.
- 50. Supersaturated Solution Asupersaturated solution is an unstable solution in which concentration of the solute is greater than when the solution is saturated.
- 51. Types of Solutions At 25oC, a saturated solution of table salt has only 36.0 g (3 tablespoons) dissolved in 100 mL of water. Any additional table salt will no longer dissolve.
- 52. Concentration of Solution TEACHER’S DEMONSTRATION Go to Link…
- 53. EXPRESSING CONCENTRATION LearningCompetency: Explains the difference between Percentage by Weight and by Volume solutions.
- 54. You can expressconcentration in other ways such as: (1) percent by volume, which is the amount of solute in a given volume of solution expressed as grams solute per 100 milliliter of solution (g/100 mL), and (2) percent by mass, which is the amount of solute in a given mass of solvent expressed as grams solute per 100 grams of solution.
- 55. Labels of productssold often show the concentrations of solutes expressed as PERCENT (%) by volume or mass. The alcohol used as a disinfectant is a solution of 70% ethyl or isopropyl alcohol, meaning 70 mL alcohol.
- 56. Vinegar is oftenlabeled as “5% acidity,” which means that it contains 5 grams of acetic acid in 100 g of vinegar.
- 57. The concentration ofsolid solutions, like gold jewelry, is expressed as karat. Pure gold is referred to as 24 karats.
- 58. Sample Problem 1 How many mL of ethyl alcohol are present in a 50 mL bottle of rubbing alcohol? 50 mL Rubbing Alcohol 푥 70 mL ethyl alcohol 100 mL rubbing alcohol = 35 mL ethyl alcohol
- 59. Sample Problem 2 A one peso coin has a mass of 5.5 grams. How many grams of copper are in a one peso coin containing 75% copper by mass? So, a 5.4 grams one peso coin contains, 5.4 g coin 75 g copper 100 g coin 푥 = 4.0 g copper
- 60. Factors Affecting HowFast a Solid Solute Dissolves
- 61. Factors Affecting HowFast a Solid Solute Dissolves Stirring or Agitation Particle Size Increase in temperature Concentration of solution Pressure on Gas Like dissolves like
- 62. The Effect ofStirring
- 63. The Effect of Stirring TEACHER’S DEMONSTRATION Go to Link…
- 64. Agitation makes thesolute dissolves more rapidly because it brings fresh solvent into contact with the surface of the solute. However, agitation affects only the rate at which a solute dissolves.
- 65. It cannot influencethe amount of solute that dissolves. An insoluble substance will remain undissolved no matter how much the system is agitated.
- 66. Also, particle sizedoes not affect solubility. It can affect the RATE at which something dissolves, but it will not change the total amount of material that can ultimately dissolve (solubility).
- 67. ACTIVITY NO. 4 SIZE MATTERS!
- 68. Particle Size Thesize does not that matters on the rate of solubility, but the area of contact.
- 69. We see thatthe dissolving of an object happens because there are collisions between the solvent and the solute. When the solute is BIG, for example a block, the solvent can only collide with the surface of the block, but not the middle of the block. that means it will take a longer time for the solvent to dissolve the solute.
- 70. When the blockis pondered into a powdery state, it is easier for the solvent to dissolve the solute because of the larger area of collisions.
- 71. ACTIVITY NO. 5 How Fast Does Coffee Dissolve in Hot Water? In Cold Water?
- 72. Temperature The solubilityof a gas in a liquid decrease with a temperature. In fact, the solubility of a gas in water is usually zero at its boiling point.
- 73. The solubility of solids and liquids is closely related to the heat of solution. The heat of solution is the heat evolved with to the surroundings, the process is exothermal and exothermic
- 74. If heat isabsorbed from the surroundings, the process is endothermal or endothermic and the heat of solution is a positive quantity.
- 75. CONCENTRATION OF SOLUTION We have already discussed concentration of solution. #1 #2 #3 #4 What do you remember?
- 76. Pressure Liquids andsolids exhibit practically no change of solubility with changes in pressure. Gases as might be expected, increase in solubility with an increase in pressure.
- 77. Henry's Law states that: The solubility of a gas in a liquid is directly proportional to the pressure of that gas above the surface of the solution.
- 78. Effect of Pressureto Solubility of Gas High Pressure Gas Molecules PRESSURE: Gas at Low Pressure Dissolved gas molecules When the gas is compressed, Gas gas molecules molecules enter can the enter liquid the more liquid frequently, and so becomes more are dissolved. dissolved.
- 79. Pressure released CokaLoca CO2 under high pressure CokaLoca Lots of CO2 dissolved in CO2 bubbles out of solution
- 80. If the pressureis increased, the gas molecules are "forced" into the solution since this will best relieve the pressure that has been applied. Carbonated beverages provide the best example of this phenomena.
- 81. Like-dissolve-like: Aptly explainsthe interaction between the solute and solvent. Polar dissolves polar
- 82. 1: Like-dissolve-like: Aptlyexplains the interaction between the solute and solvent. Polar dissolves polar Non-polar dissolves non polar
- 83. What have youlearned? Now that you have completed the activities in this module, you have learned the properties of a solution, the ways of reporting its concentration, as well as the effects of stirring, particle size, temperature, and type of solute on how fast a solid dissolves in water. While learning about solutions, you also had the chance to gather information and gain new knowledge through the process of conducting science investigations. You also learned the importance of identifying the variables that had to be controlled in order to make a good plan for measuring and testing the variables you are concerned about. What you have started doing in these investigations is what scientists usually do when they seek answers to a scientific question or problem. In the next modules, you will be challenged to ask more questions about materials around you. You will try to explain answers to your hypothesis (your suggested explanation) after you have done your investigation.
- 84. SUMMARY: SOLUTIONis a system in which one or more substances are homogenous mixed. A solution has two (2) components: SOLUTE AND SOLVENT. SOLUBILITY is the maximum amount of solute that dissolves in a given amount of solvent at a specified temperature. The 6 factors that affect solubility are: (a) Stirring or Agitation (b) Particle Size (c) Increase in temperature, (d) Concentration of solution (e) Pressure on Gas (f) Like dissolves like. The concentration of solution expresses the amount of solute dissolved in a given quantity of solvent: Concentration can be expressed in different ways: As dilute or concentrated As saturated, unsaturated, and supersaturated Percent by weight, percent by volume, or percent by weight/volume.
- 85. QUIZZES KNOWLEDGE: Process: Understanding: Oral Recitation: Pre/Post Test
- 86. DANIEL CORTON TABINGA,JR. © 2014
Editor's Notes
- #2 Katahimikan Atensyon Pagtutok Isulat Tumingin Magmasid Umugnay Sa mga gawain ‘
- #3 This set of five modules on the Diversity of Materials in the Environment provides many opportunities for students to increase their understanding of solutions, substances and mixtures, elements and compounds, acids and bases, and metals and nonmetals, through engaging them in scientific inquiry. There is a wide range and variety of materials on Earth. These include natural materials, those that have been made from other materials (processed or manufactured), and those which make up living things. In Grade 7, the development of ideas about materials begins with awareness of solutions, which students often encounter everyday as liquid mixtures. Further awareness of materials in terms of the components they are made of— substances, elements, compounds are taken up in Modules 2, 3, and 5. Students will also study the properties of a special group of compounds—acids and bases in Module 4. These concepts will be encountered by the students in the contexts and life situations that they are most familiar with. It is important to recognize that the teaching of the concepts covered in this set of modules focuses more on the „macro‟ view (the tangible and visible). Science education research recommends that concepts be taught, initially, at the macro level only. Explanations at the „submicroscopic‟ level (atomic or molecular level) could be shared in appropriate doses enough to be processed by the students. The use of chemical symbols and equations are reserved for higher grade levels much later. The experiences gained through different activities in each module will allow students to transform the information they obtain into a form that is usable to them in their own personal and community context. The development of the modules veers away from teaching science that is textbook-centered to that which incorporates interactive and inquiry-based learning experiences. Inquiry is essential in learning science. When students are engaged in inquiry, they describe objects and phenomena, “identify questions that can be answered through scientific investigations; design and conduct a scientific investigation; use appropriate tools and techniques to Grade 7 Science: Matter Diversity of Materials in the Environment ii gather, analyze, and interpret data; develop descriptions, explanations, predictions, and models using evidence; think critically and logically to make the relationships between evidence and explanations; recognize and analyze alternative explanations and predictions; communicate scientific procedures and explanations; and use mathematics in all aspects of scientific inquiry” (TheNational Science Education Standards, U.S. National Research Council, 2000. p.19). Research has shown that the use of inquiry and investigative skills develop with age. In this set of modules, the students will apply the inquiry skills they learned in earlier grades. They will plan and carry out simple science investigations. Each student will be able to participate first-hand in looking for evidence to answer questions they have posed at the beginning. They will have opportunities to gather and interpret data as well as draw conclusions based on evidence they have gathered. They will perform fair tests by identifying variables to be changed, measured and controlled, and do repeat trials. The teacher needs to guide and intervene throughout the process of investigation to improve the students‟ understanding of the concepts involved. Gradually, the students will gain more independence in looking for evidence to answer questions as they move from guided inquiry to full investigations. It is hoped that through the use of inquiry, teachers will be able to facilitate learning of science and assess each student’s developing understandings and abilities. Some activities, by themselves, can be considered as embedded assessment. There is also a pre/post test that should be administered before and after all the activities in each module have been completed. The teacher needs to analyze the results of these tests. The pretest results will indicate students‟ prior knowledge and alternative conceptions (if any). The posttest results will show the extent of students‟ comprehension of the concepts and their capacity to demonstrate needed skills. The posttest can also reveal students‟ misconceptions that need to be addressed in succeeding modules.
- #11 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #12 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #13 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information What is matter? Matter is anything that takes up space and has a mass.
- #14 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information Do you know that chairs, plates, air, wood, water, mud, sea and birds have one thing in common? They are all classified as matter! So, what is matter? Can we say that all the things around us are examples of matter?
- #15 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #16 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #17 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information A book, your body, a rock, the heavenly bodies, milk, bacteria, carbon dioxide in soda, carbon monoxide in automobile exhaust pipes are examples of matter. Solids are: Books, Spoon, Cell phone Dry Ice
- #18 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information A book, your body, a rock, the heavenly bodies, milk, bacteria, carbon dioxide in soda, carbon monoxide in automobile exhaust pipes are examples of matter. Liquid are: Water Vinegar Alcoholic drinks Soy sauce Cooking Oil
- #19 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information A book, your body, a rock, the heavenly bodies, milk, bacteria, carbon dioxide in soda, carbon monoxide in automobile exhaust pipes are examples of matter. Solids are: Smoke Smog Clouds Fog Oxygen
- #20 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information A book, your body, a rock, the heavenly bodies, milk, bacteria, carbon dioxide in soda, carbon monoxide in automobile exhaust pipes are examples of matter. Solids are: Ice cream Jello Yugart Cream Gel
- #21 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #22 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information How can you change the state of material into another state? If you place some ice cubes in a beaker and allow it to stand for thirty minutes, what can we expect to see? The ice will melt, that is, changes into water. Here you see a solid changing to liquid. This process may be presented by this simple equation.
- #23 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information Learning Objectives: Define solution, solute, solvent, solubility, soluble, insoluble, miscible, and immiscible.
- #24 Teacher Reading/ Activity In this module on Solutions, the activities have been sequenced in such a way that the concepts are developed gradually from the first to the last activity. It starts with the students being acquainted with solutions found in their home. The second activity allows them to study the common characteristics of solutions—appearance, number of phases observed, ability to be dissolved in water, and ability to be filtered. In Activity 3, students begin to distinguish a saturated from an unsaturated solution through a guided investigation where they learn that there is a maximum amount of solute that can dissolve in a given amount of solvent at a certain temperature. ________________________________________ Student Reading/Activity In Grade 6, you have learned about different mixtures and their characteristics. You have done activities where you mixed a solid and a liquid or combined two different liquids. In the process of mixing, you have observed that these mixtures either form homogeneous or heterogeneous mixtures. You have seen that when all parts of the mixture have the same uniform appearance and properties, it is homogeneous. You also learned that when different parts of the mixture can be identified, it is heterogeneous. An example of a heterogeneous mixture is ice cubes (solid phase) placed in a glass of soft drink (liquid phase). Different phases can be identified. When all the ice cubes are melted, only one liquid phase is seen. It is now homogeneous. Homogeneous mixtures are called solutions. When you put sugar into water, the solid becomes part of the liquid and cannot be seen. You can say that the sugar dissolves in water or the sugar is soluble in water. Solutions may be solids dissolved in liquids or gases dissolved in liquids. There are also solutions where a gas is dissolved in another gas, a liquid in another liquid or a solid in another solid. Gaseous, liquid, and solid solutions are all around you. Many commercial products are sold as solutions. ________________________________________ About the Slide ________________________________________ Other Information
- #25 Teacher Reading/ Activity In this module on Solutions, the activities have been sequenced in such a way that the concepts are developed gradually from the first to the last activity. It starts with the students being acquainted with solutions found in their home. The second activity allows them to study the common characteristics of solutions—appearance, number of phases observed, ability to be dissolved in water, and ability to be filtered. In Activity 3, students begin to distinguish a saturated from an unsaturated solution through a guided investigation where they learn that there is a maximum amount of solute that can dissolve in a given amount of solvent at a certain temperature. ________________________________________ Student Reading/Activity You have seen that when all parts of the mixture have the same uniform appearance and properties, it is homogeneous. You also learned that when different parts of the mixture can be identified, it is heterogeneous. An example of a heterogeneous mixture is ice cubes (solid phase) placed in a glass of soft drink (liquid phase). Different phases can be identified. When all the ice cubes are melted, only one liquid phase is seen. It is now homogeneous. Homogeneous mixtures are called solutions. When you put sugar into water, the solid becomes part of the liquid and cannot be seen. You can say that the sugar dissolves in water or the sugar is soluble in water. Solutions may be solids dissolved in liquids or gases dissolved in liquids. There are also solutions where a gas is dissolved in another gas, a liquid in another liquid or a solid in another solid. Gaseous, liquid, and solid solutions are all around you. Many commercial products are sold as solutions. ________________________________________ About the Slide In this module, you will identify common properties of solutions using different methods. You will also learn how to report the amount of the components in a given volume of solution. Towards the end of the module, you will investigate the factors that affect how fast a solid dissolves in water. At the end of Module 1, you will be able to answer the following key questions. ________________________________________ Other Information
- #26 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #27 Teacher Reading/ Activity For the TEACHER 1. Assign your students to go to a store or grocery and list the products being sold. Ask them to identify which among the products are solutions. 2. Let the students describe the products in terms of color and appearance, odor, feel, and taste (for food products). 3. They may also search their kitchen shelves and storage areas at home to identify the solutions they use at home. Let the students bring the product itself or the label of the used product. 4. Bring to class other solutions which students may not recognize as solutions. Some examples are bronze medal, brass, stainless steel utensils, sterling silver jewelry, coins, and other solutions. ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ The development of inquiry skills is also gradual. In Activity 1, the students will simply write observations and present their observations in table form. In the second activity, students will predict, find some patterns and draw conclusions based on the collected data in order to give the common characteristics of solutions. Students will have the opportunity to observe, measure, analyze data and consequently give generalizations when they distinguish between a saturated and an unsaturated solution in Activity 3. Activities 4 to 6 deal with factors affecting how fast a solid solute dissolves in water. Students will perform a guided investigation where they will (1) formulate specific question(s) to a testable form; (2) formulate a hypothesis that identifies a cause and effect relationship between the dependent and independent variables; (3) select and justify a procedure to be used in answering the specific question(s); (4) identify the dependent and independent variables in the investigation; (5) carry out the procedure that includes a fair test, including controlling variables and doing repeated trials to increase accuracy and reliability; (6) make observations that are relevant to the specific question(s); (7) make measurements using appropriate devices; (8) record and report all observations and data; (9) interpret patterns from the data gathered; (10) infer and explain relationships from the data; and (11) draw a conclusion from the results obtained, including a statement to support or reject the hypothesis.
- #28 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #29 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #30 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #32 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information Do you know that there are several types of solution?
- #33 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #34 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #35 All gases are soluble in one another. Recall the composition of air. It consist of about 18 gases in different proportions. Some industrial waste are gaseous solutions like SO2, H2S,NO2, CO2, and CO.
- #36 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information In our experience, a solution is generally liquid because this is its most common form. Solutions in the biological system and in the environment are in liquid form.
- #37 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information Solutions like ethanol in which water is the solvent, are called aqueous solution. Ethanol is used as solvent for perfumes, print ink, and glue.
- #38 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #39 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #41 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information Solid solutions have numerous applications. An alloy, a mixture of elements that have an overall metallic characteristics, is an example of solid-solid solution. Steel and brass have numerous applications in industries.
- #42 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information Examples of solutions that occur naturally are natural bodies of water like the seas and ocean, blood plasma, air, and some mineral ores. Many materials in nature can be used efficiently only when these are in the form of solutions. For example, plants cannot absorb minerals from the soil unless these minerals are in solution. Components of the food that you eat go into solution during digestion. The nutrient particles in solution can pass through the digestive tract and dissolve in the blood. Seawater is a solution having a higher percentage of salt and minerals than other sources of water like ground water or rivers. Rainwater is a solution containing dissolved gases like oxygen and carbon dioxide. The water you drink contains dissolved minerals like sodium, potassium, magnesium and calcium and dissolved gases like oxygen and carbon dioxide. Air is a mixture of gases. Dry air consists of about 78% nitrogen, 21% oxygen, 1% argon, about 1% water vapor, 0.04% carbon dioxide and traces of argon, helium, neon, krypton, and xenon. Water vapor is present in different amounts depending on the location. Air above big bodies of water contains more water vapor than air above deserts. Humidity is a measure of the amount of water vapor in air. Useful solutions are found not only in nature; many solutions are made for a specific purpose.
- #43 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information Almost every household uses vinegar for cooking and cleaning purposes. Vinegar usually contains about 5% acetic acid in water. Some vinegar are clear homogeneous mixtures (solutions). Other kinds of vinegar are colloidal. Gasoline is a solution made up of different substances called hydrocarbons. It is important that gasoline contains no solid particles that may clog the vehicle engine. A metal alloy is a solid solution made up of two or more metals or non metals. For example, steel is an alloy of copper and tin. Brass is an alloy of copper and zinc. Other examples of solutions that are processed include wine and liquor, brewed coffee and tea. In the next activity, you will predict what will happen when you mix a sample solid or liquid in a given volume of water. Investigate to find out if your predictions are correct. Explain your predictions using the evidence you have gathered from your investigation.
- #44 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information Many solids are really solid solutions. For example, steel is a solution in which carbon is dissolved in iron. The carbon is dissolved in iron. The carbon dissolves in the iron when the iron is melted. When the iron cools and changes back into a solid steel. Solid solution are often called alloys, like brass (cooper and zinc).
- #45 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information Water can dissolve more solutions than any other liquid, so it is called the universal solvent. Usually, a solid solute is dissolved in liquid solvent like salt solution (sodium chloride dissolved in water). Gas can also dissolve in liquids to make liquids to make a liquid solution.
- #46 Teacher Reading/ Activity ________________________________________ Student Reading/Activity Examples of solutions that occur naturally are natural bodies of water like the seas and ocean, blood plasma, air, and some mineral ores. Many materials in nature can be used efficiently only when these are in the form of solutions. For example, plants cannot absorb minerals from the soil unless these minerals are in solution. Components of the food that you eat go into solution during digestion. The nutrient particles in solution can pass through the digestive tract and dissolve in the blood. Seawater is a solution having a higher percentage of salt and minerals than other sources of water like ground water or rivers. Rainwater is a solution containing dissolved gases like oxygen and carbon dioxide. The water you drink contains dissolved minerals like sodium, potassium, magnesium and calcium and dissolved gases like oxygen and carbon dioxide. Air is a mixture of gases. Dry air consists of about 78% nitrogen, 21% oxygen, 1% argon, about 1% water vapor, 0.04% carbon dioxide and traces of argon, helium, neon, krypton, and xenon. Water vapor is present in different amounts depending on the location. Air above big bodies of water contains more water vapor than air above deserts. Humidity is a measure of the amount of water vapor in air. Useful solutions are found not only in nature; many solutions are made for a specific purpose. ________________________________________ About the Slide ________________________________________ Other Information
- #47 Teacher Reading/ Activity ________________________________________ Student Reading/Activity Almost every household uses vinegar for cooking and cleaning purposes. Vinegar usually contains about 5% acetic acid in water. Some vinegar are clear homogeneous mixtures (solutions). Other kinds of vinegar are colloidal. Gasoline is a solution made up of different substances called hydrocarbons. It is important that gasoline contains no solid particles that may clog the vehicle engine. A metal alloy is a solid solution made up of two or more metals or non metals. For example, steel is an alloy of copper and tin. Brass is an alloy of copper and zinc. Other examples of solutions that are processed include wine and liquor, brewed coffee and tea. In the next activity, you will predict what will happen when you mix a sample solid or liquid in a given volume of water. Investigate to find out if your predictions are correct. Explain your predictions using the evidence you have gathered from your investigation. ________________________________________ About the Slide ________________________________________ Other Information
- #48 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #50 Teacher Reading/ Activity Grade 7 students are not expected to use these solubility curves, which will be taken up in Grade 9. The effect of temperature on the solubility of gases in liquids will also be taken up also in Grade 9. ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #52 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #53 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #54 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information The solution that contains the maximum amount of solute dissolved by a given amount of solvent is called a saturated solution. If you add more solute to the solvent, it will no longer dissolve. The solution has reached its saturation point. The presence of an excess solid which can no longer dissolve is evidence that the solution is saturated.
- #55 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information A solution is unsaturated when it contains less solute than the maximum amount it can dissolve at a given temperature. In Activity 3 Part A, it is difficult to conclude that the containers with all solids dissolved are unsaturated simply by observing them. Some of these may already hold the maximum amount of solute, which cannot be observed by the unaided eye. If they do, then these are classified as saturated solutions.
- #56 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information A solution is unsaturated when it contains less solute than the maximum amount it can dissolve at a given temperature. In Activity 3 Part A, it is difficult to conclude that the containers with all solids dissolved are unsaturated simply by observing them. Some of these may already hold the maximum amount of solute, which cannot be observed by the unaided eye. If they do, then these are classified as saturated solutions.
- #57 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #58 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #59 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information
- #60 Teacher Reading/ Activity ________________________________________ Student Reading/Activity ________________________________________ About the Slide ________________________________________ Other Information A more measurable way to find out the solubility of a solute is to determine the maximum amount that can be dissolved in 100 g of solvent at a specific temperature. There are available data from chemistry books that give the solubility of common solutes at particular temperatures. Figure 2 shows the solubility of table salt at 25oC.
- #61 Main Idea: The concentration of a solution depends on the amount of solute dissolved in a given amount of solvent. EQ: Why is 0.9% sodium chloride solution used in intravenous injection?
- #62 Main Idea: The concentration of a solution depends on the amount of solute dissolved in a given amount of solvent. EQ: Why is 0.9% sodium chloride solution used in intravenous injection?
- #63 Now that you have distinguished dilute from concentrated solutions qualitatively and quantitatively from your teacher’s demonstration, you can express concentration in other ways such as: (1) percent by volume, which is the amount of solute in a given volume of solution expressed as grams solute per 100 millliter of solution (g/100 mL), and (2) percent by mass, which is the amount of solute in a given mass of solvent expressed as grams solute per 100 grams of solution. Labels of products sold often show the concentrations of solutes expressed as percent (%) by volume or mass. The alcohol used as a disinfectant is a solution of 70% ethyl or isopropyl alcohol, meaning 70 mL alcohol. There are also solutions sold as 40% ethyl or isopropyl alcohol. Vinegar is often labeled as “5% acidity,” which means that it contains 5 grams of acetic acid in 100 g of vinegar. The common antiseptic, agua oxinada is a 3% solution, that is, 3 grams hydrogen peroxide in 100 mL water. The concentration of solid solutions, like gold jewelry, is expressed as karat. Pure gold is referred to as 24 karats. Jewelry that is said to be 18 karats contains 18 grams of gold for every 24 grams of the material, 6 grams Grade 7 Science: Matter 11 Diversity of Materials in the Environment consist of the other metal like copper or silver. This material has a concentration of 75% gold, that is, [18/24(100)]. A 14 karat (14K) gold contains 14 grams gold and 10 grams of another metal, making it 58.3% gold. The following sample problems show you that there is a way to know the exact ratio of solute to solvent, which specifies the concentration of a solution.
- #64 Labels of products sold often show the concentrations of solutes expressed as percent (%) by volume or mass. The alcohol used as a disinfectant is a solution of 70% ethyl or isopropyl alcohol, meaning 70 mL alcohol. There are also solutions sold as 40% ethyl or isopropyl alcohol.
- #65 Vinegar is often labeled as “5% acidity,” which means that it contains 5 grams of acetic acid in 100 g of vinegar. The common antiseptic, agua oxinada is a 3% solution, that is, 3 grams hydrogen peroxide in 100 mL water.
- #66 The concentration of solid solutions, like gold jewelry, is expressed as karat. Pure gold is referred to as 24 karats. Jewelry that is said to be 18 karats contains 18 grams of gold for every 24 grams of the material, 6 grams consist of the other metal like copper or silver. This material has a concentration of 75% gold, that is, [18/24(100)]. A 14 karat (14K) gold contains 14 grams gold and 10 grams of another metal, making it 58.3% gold.
- #67 Calculation for sample problem 1 Since rubbing alcohol contains 70% ethyl alcohol, it means that 100 mL of rubbing alcohol contains 70 mL ethyl alcohol. So, the following calculations show that in 50 mL of rubbing alcohol, there is 35 mL ethyl alcohol. All portions of a solution have the same concentration. The composition of one part is also the same as the composition of the other parts. But you can change the concentration of solutions. This means you can prepare different solutions of sugar in water of different concentrations (for example, 10%, 20%, or 30%). In the same way, you can prepare different solutions of salt in water.
- #68 Calculation for sample problem 2 75% by mass means 75 grams of copper in 100 grams of one peso coin.
- #72 Main Idea: The concentration of a solution depends on the amount of solute dissolved in a given amount of solvent. EQ: Why is 0.9% sodium chloride solution used in intravenous injection?
- #86 The effect of pressure on the solubility of the gas was studied by William Henry. He observed that at constant temperature, the solution of gas is directly proportional to the pressure of the gas In equilibrium with the solution. Known as Henry’s Law.
- #87 When the gas is compressed, the pressure above the gas will force the gas molecules into the solution. This will allow more gas to dissolve. This allow will more gas to dissolve. This is how carbonated beverages are made. A pressure of 2 to 5 atm is applied to carbonated drinks to increase the solubility of CO2 in the solution. When you open the can, the pressure is reduced to 1 atm, reducing the solubility of carbon dioxide. Carbon dioxide molecules come “bubbling out” of solution. When most of the CO2 has escaped, the drink taste “flat”.
- #88 The effect of pressure on the solubility of the gas was studied by William Henry. He observed that at constant temperature, the solution of gas is directly proportional to the pressure of the gas In equilibrium with the solution. Known as Henry’s Law. Henry’s Law explains the decompression sickness, (also called bends), scuba divers may experience upon surfacing from dive. Scuba divers who breath compressed air and dive 50 ft. below have more N2 gas dissolved in their blood. If they ascend quickly, the dissolve N2 bubbles out of the blood as it escapes from the solution. Bends is extremely painful and can be fatal.
- #91 Example: Carbon tetrachloride with gasoline