General Chemistry 2 - Colegio de los Baños - 2024-2025 PDF

GENERAL CHEMISTRY 2 Level: SENIOR HIGH SCHOOL Semester: FIRST Subject Group: SPECIALIZED SUBJECT (STEM) Quarter: FIRST Course Description: This course focuses on intermolecular forces of liquids and gases, ph...

GENERAL CHEMISTRY 2 Level: SENIOR HIGH SCHOOL Semester: FIRST Subject Group: SPECIALIZED SUBJECT (STEM) Quarter: FIRST Course Description: This course focuses on intermolecular forces of liquids and gases, physical properties of solutions, chemical kinetics, chemical equilibrium, acid-base and salt solution equilibria, thermochemistry, chemical and electrochemistry. Course Requirements: Below are the list of activities that must be completed and submitted with their corresponding percentage. Date of Raw Score Checked WEEK ACTIVITIES Completion by Enabling Assessment Activity 1- Intermolecular /20 1 Forces of Attraction Performance Check – Laboratory Activity No. 1: /50 2 Properties of Liquids Enabling Assessment Activity 2- Phase Changes and /35 3 Phase Diagrams Enabling Assessment Activity 3 – Concentration /40 4 Measures Performance Check – Laboratory Activity No. 2: /50 4 Colligative Properties Performance Check – Laboratory Activity No. 3: /50 5 Factors Affecting the Rate of Reaction Enabling Assessment Activity 4 – Chemical /35 6 Equilibrium Enabling Assessment Activity 5 – Le Chatelier’s /20 7 Principle TOTAL EAA TOTAL Performance Check GRADING SYSTEM Enabling Assessment Activities 30% Quarterly Exam 20% Performance Tasks 50% TOTAL 100%  1 Colegio de los Baños – GENERAL CHEMISTRY 2 Prerequisite Assessment A. Recall the states or phases of matter and their macroscopic properties. 1. Can you tell why solids are compact and rigid? 2. Why are liquids able to follow the shape of the container? 3. Why do gases easily dissipate? B. What are the different chemical bonds or intramolecular forces of attraction? Learning Materials: Module, pen, paper, chemistry books, internet (if applicable) Prerequisite Content-knowledge: States of matter and their macroscopic properties Prerequisite Skill: Differentiate the macroscopic properties of the states of matter INTRODUCTION: A. TIME ALLOTMENT: 4 hours (synchronous and asynchronous) B. CONSULTATION: For questions and clarifications, you may consult your subject teacher on the assigned schedule. C. RUA: At the end of the lesson, you should be able to:  Use the kinetic molecular model to explain properties of liquids and solids  Describe and differentiate the types of intermolecular forces  Describe the difference in structure of crystalline and amorphous solids  Describe the different types of crystals and their properties: ionic, covalent, molecular, and metallic. D. INSTITUTIONAL VALUES: Critical Thinking Learners will be able to apply critical thinking in:  Identifying the intermolecular forces of attractions in solids and liquids and  Analyzing how chemical properties of solids such as melting point, boiling point, solubility and reactivity are affected by the dominant intermolecular forces present. E. OVERVIEW OF THE LESSON This lesson is about how kinetic molecular theory explains properties of liquids and solids. This also includes the discussion on the different types of intermolecular forces of attraction, differentiation on the different types of solids. STUDENT’S EXPERIENTIAL LEARNING Individual Reading Chunk 1: The Molecular View of Liquids and Solids Formative Question: What is the behavior of the particles as explained by the kinetic molecular theory? Matter can exist in the following states, or phases: However, the focus for this course will be for solid, solid, liquid, gas, plasma and bose Einstein. liquid and gas. The figure shows the particles for these phases.  2 Colegio de los Baños – GENERAL CHEMISTRY 2 Figure 1. Macroscopic view of solid, liquid and gas The Condensed State: Liquids and Solids For Gases In liquids, the molecules are so close together that An increase in temperature results in increased there is very little empty space between them. Liquids kinetic energies of gases dissolved in liquids. This are much more difficult to compress and they are increased motion enables the dissolved gas to break much denser at normal conditions. intermolecular forces with the solvent, and escape the Molecules in a liquid are held together by one or solution. more types of attractive forces. However, the Thus, a warm bottle of carbonated drink/ soft drink molecules can move past one another freely. Liquids does not taste as good as a cold one, because there can flow, can be poured and assumes the shape of its is less CO2 dissolved in the warm bottle. container. In a solid, molecules are held tightly in position with virtually no freedom of motion. There is even less empty space in a solid than in a liquid. Solids are almost incompressible and possess definite shape and volume. Chunk 2. Forces Of Attraction Formative Question: How to identify which IMFA is predominant in a liquid? Intramolecular Forces of Attraction VS Intermolecular Forces of Attraction  Also referred to as chemical bonding  Also referred to as the van der Waals forces.  Types: ionic, covalent, metallic  Types: London Dispersion Forces, dipole-dipole  Very strong forces that can also be broken at forces, and hydrogen bonds, ion-dipole forces high temperatures  weaker attractions that hold molecules or noble gas This has been discussed in General Chemistry 1 particles close together when they are in a liquid or solid form. Intermolecular Forces of Attraction London Dispersion Forces – Dipole-Dipole Forces – exists between neutral polar molecules which are very close together  3 Colegio de los Baños – GENERAL CHEMISTRY 2 Hydrogen Bonding – exists between the hydrogen Ion-Dipole Forces – exists between an ion and atom in a polar bond and an unshared electron pair partial charge at one end of a polar molecule (dipoles) on a nearby electronegative ion or atom hydrogen bond with F, N, and O is polar The figure below may be used as guide to identify the IMFA in a substance. (Source: General Chemistry 2 TG) This table summarizes the different types of IMFA (Source: General Chemistry 2 TG)  4 Colegio de los Baños – GENERAL CHEMISTRY 2 Chunk 3: Solids Formative Question: How are do intermolecular forces of attraction affect the type of solid? Solids can be categorized into two groups: Crystalline solids Amorphous(Noncrystalline) solids Charcoal rubber bands glass plastics Pyrite Fluorite Amethyst Arrangement fixed geometric patterns or lattices. random orientation of particles. of Molecules Behavior when  crystals become liquids at a specific  soften gradually when they are heated. heated temperature (i.e. the melting point). tend to melt over a wide range of temperature.  physical properties of the crystalline solids change sharply. Types of Crystalline Solids Metallic Ionic Molecular Covalent Network Forms of atoms Cations and anions Atoms or molecules Atoms connected in Unit Particles a network of covalent bonds Forces Metallic bonds Electrostatic London Dispersion Covalent bonds Between Attraction Forces particles Dipole-dipole Hydrogen bonds Properties Hardness Soft to very hard Hard and brittle Fairly soft Very hard Melting point Low to very high High Low to moderately high Very high Electrical & Excellent Poor thermal Poor Poor conductivity Examples All metallic elements; Typical salts; NaCl, Argon (Ar) Diamond, quartz Cu, Fe, Al, Pt Ca(NO3)2 Methane (CH4) Sucrose(C12H22O11) Additional References: http:// www.mhhe.com/physsci/chemistry/essentialchemistry http:// www.khanacademy.com  5 Colegio de los Baños – GENERAL CHEMISTRY 2 Name: ___________________________________________ Section: _______________________________ LAST NAME, FIRST NAME MIDDLE INITIAL ENABLING ASSESSMENT Activity NO. 1 - INTERMOLECULAR FORCES OF ATTRACTION ENGAGEMENT (Group Activity) INTERMOLECULAR FORCES OF ATTRACTION IN LIQUIDS Score: _____________/10 Direction: Identify the strongest IMFA present in the following compounds and mark ✓. (Only one mark per row) LIQUIDS MOLECULES IONS Nonpolar Polar Polar IONS & IONS molecules molecules with POLAR ONLY H bonded with MOLECULES F/O/N LDF Dipole-Dipole Hydrogen Ion Dipole Ionic bond Bond 1. water (H2O) 2. ethane (C2H6) 3. NaCl in water 4. KCl 5. carbon tetrachloride (CCl4) Direction: Identify the strongest IMFA present in the following compounds and write on the blank. Examine the elements in the compound. Identify the intramolecular bond (ionic/metallic/covalent) For covalently bonds, identify the IMFA (Dispersion/ Dipole-Dipole/ Hydrogen Bonds) SOLIDS TYPES OF CRYSTALS Molecular Metallic Ionic Covalent Network London Dipole-dipole Hydrogen Metallic Bond Ionic Bond Covalent Dispersion Bond Bond 1. HF 2. NO 3. Li2S 4. Al 5. Kr  6 Colegio de los Baños – GENERAL CHEMISTRY 2 ASSIMILATION (Individual Activity) INTERMOLECULAR FORCES OF ATTRACTION IN SOLIDS Score: _______/10 Direction: Identify the strongest IMFA present in the following compounds and mark ✓. (Only one mark per row) LIQUIDS MOLECULES IONS Nonpolar Polar Polar IONS & IONS molecules molecules with POLAR ONLY H bonded with MOLECULES F/O/N LDF Dipole-Dipole Hydrogen Ion Dipole Ionic bond Bond 1. LiCl in water 2. KBr 3. carbon tetrafluoride (CF4) 4. ammonia(NH3) 5. methanol (CH3OH) Direction: Identify the strongest IMFA present in the following compounds and write on the blank. Examine the elements in the compound. Identify the intramolecular bond (ionic/metallic/covalent) For covalently bonds, identify the IMFA (Dispersion/ Dipole-Dipole/ Hydrogen Bonds) SOLIDS TYPES OF CRYSTALS Molecular Metallic Ionic Covalent Network London Dipole-dipole Hydrogen Metallic Bond Ionic Bond Covalent Dispersion Bond Bond 1. SO2 2. MgO 3. KMnO4 4. Cu 5. Graphite  7 Colegio de los Baños – GENERAL CHEMISTRY 2 Prerequisite Assessment A. Differentiate the intermolecular forces of attraction. B. Give examples of liquids and the dominant intermolecular forces of attraction. Learning Materials: Module, pen, paper, chemistry books, internet (if applicable) Prerequisite Content-knowledge: Intermolecular forces of attraction in liquids Prerequisite Skill: Identify the intermolecular forces of attraction in liquids INTRODUCTION: A. TIME ALLOTMENT: 4 hours B. CONSULTATION: For questions and clarifications, you may consult your subject teacher on the assigned schedule. C. RUA: At the end of the lesson, you should be able to:  explain the properties of water with its molecular structure and intermolecular D. INSTITUTIONAL VALUES: Critical Thinking and Social Responsibility  Learners will be able to apply critical thinking in: Analyzing how chemical properties of solids and liquids such as chemical properties of molecules such as melting point, boiling point, solubility and reactivity are affected by the dominant intermolecular forces present.  Learners will be able to apply social responsibility in: Water conservation upon learning its usefulness as a universal solvent. E. OVERVIEW OF THE LESSON This lesson is about the different properties of liquids, how they are affected by intermolecular forces of attraction and about the importance of water as the universal solvent. STUDENT’S EXPERIENTIAL LEARNING Individual Reading CHUNK 1: Properties of Liquids and Intermolecular Forces Focus Question: How are the properties of liquids affected by intermolecular forces? Liquids and solids are referred to as the condensed Liquids and gases are fluids because molecules states because their molecules are very close can move past each other even though they cannot together. get very far from each other. 1. Surface tension  is the measure of the elastic force in the surface of a liquid.  is the amount of energy required to stretch or increase the surface of a liquid by a unit area.  is manifested as some sort of skin on the surface of a liquid or in a drop of liquid.  ↑IMFA ↑surface tension  Example: water has ↑surface tension because of Hydrogen bonding https://sciencewithkids.com  8 Colegio de los Baños – GENERAL CHEMISTRY 2 2. Viscosity  is a measure of a fluid’s resistance to flow. The greater the viscosity, the slower the liquid flows.  is expressed in units of centipoise. The table below gives viscosities of liquids of some pure substances.  Water has viscosity of 1 centipoise or 0.001 Pa/s at 20oC.  is affected by temperature, (↑temperature ↓viscosity)  ↑IMFA ↑ viscosity  Example: https://www.petro-online.com Viscosity of H2O: 1 centipoise Viscosity of Honey: 10,000 centipoise IMFA of honey > IMFA of H2O 3. Capillary Action  is the tendency of a liquid to rise in A doctor takes blood sample from narrow tubes or be drawn into a patient’s finger using a capillary small openings such as those tube. (Image Source: between grains of a rock. https://www.colourbox.com/  also known as capillarity  is a result of intermolecular attraction between the liquid and solid materials.  Two types of forces are involved in capillary action: Concave and Convex Meniscus. (Image Source:  Cohesion is the intermolecular http://www.diffen.com/difference/ attraction between like Adhesion_vs_Cohesion) molecules (the liquid molecules).  Adhesion is an attraction between unlike molecules (such as those in water and in the particles that make up the glass tube). 4. Vapor pressure  is the pressure exerted by the gas in equilibrium with a liquid in a closed container at a given temperature  increases with temperature.  is independent of the amount of liquid as well as the surface area of the liquid in contact with the gas.  ↑temperature ↑ vapor pressure  ↑IMFA ↓vapor pressure  Examples: Vapor pressure at 25oC Evaporation of water in open and in closed containers acetone: 0.28atm (Image Source: http:// H2O: 0.03 atm boomeria.org/physicslectures/heat/equilibrium.jpg) Acetone evaporates faster than water because its IMFA is weaker than that of water. Water’s IMFA is stronger because of its hydrogen bonding.  9 Colegio de los Baños – GENERAL CHEMISTRY 2 5. Molar Heat of Vaporization ∆HVap and Boiling Point  is the energy required to vaporize 1 mole of a liquid at a given temperature.  ↑IMFA ↑∆HVap & ↑Boiling Point  Example: BP ∆HVap o H2O: 100.0 C 40.79 kJ/mol Ethyl Alcohol:78.3 oC 39.3 kJ/mol IMFA of water is stronger than alcohol that is why boiling point is higher and ∆HVap is also greater than that of Ethyl alcohol. Chunk 2. The Unique Properties of Water (H2O) Focus Question: Why is water a universal solvent? Property Description Environmental Effect Water is a  It dissolves salts and other ionic  Plants are able to absorb nutrient ions good compounds, as well as polar covalent dissolved in water. solvent. compounds and substances that are  Issues can be caused however by the ease capable of forming hydrogen bonds with of which pollutants from farming and water. industrial plants are dissolved.  Gases like oxygen and carbon dioxide will dissolve in water meaning that some animals do not need to breathe air in order to respire.  Water is sometimes called the universal solvent because it  can dissolve so many things. Water has a  Specific heat is the amount of heat or  In summer months, bodies of water absorb high specific energy needed to raise the temperature of a great deal of energy in the form of heat heat. one gram of a from the sun in order for the temperature to substance by 1oC. increase. It provides an almost constant The specific heat of water is 1 calorie/g- temperature for the plants and animals living oC (4.18 J/g-oC), one of the highest for there. many liquids.  It takes about 4.5 times greater amount of  Water can absorb a large amount of heat energy to heat up water than an equal even if its temperature rises only slightly. amount of land.  Hence, large bodies of water heat up and cool down more slowly than adjacent land masses. The boiling  Many compounds similar in mass to water  Small water bodies like ponds are at risk of point of have much lower boiling points. drying up in the summer. But since the water  The strong intermolecular forces in water amount of energy required to vaporize or unusually allow it to be a liquid at a large range of evaporate water is so high, this is prevented high. temperatures. from happening quickly. Solid water  Unlike all other liquids, the molecules in  Because ice floats, aquatic organisms is less dense, solid water are actually farther apart than survive under the surface, which remain and in fact they are in liquid water. liquid. floats on  When solid water forms, the hydrogen  The ice surface also acts as an insulating liquid water. bonds result in a very open structure with layer protecting the water beneath from unoccupied spaces, causing the solid to further freezing, and maintains a temperature occupy a larger volume than the liquid.. adequate for survival. Additional References: http:// www.mhhe.com/physsci/chemistry/essentialchemistry http:// www.khanacademy.com  10 Colegio de los Baños – GENERAL CHEMISTRY 2 Name: _______________________________________ Section: ________________ LAST NAME, FIRST NAME MIDDLE INITIAL PERFORMANCE CHECK LABORATORY ACTIVITY NO. 1: PROPERTIES OF LIQUIDS AND IMFA ENGAGEMENT Score: ____________/10 (Pre-Lab - Individual). INTRODUCTION (3-5 sentences) Enumerate how the following properties are affected by the IMFA present in a liquid. What is the importance of learning about the properties of liquids? __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ (In-Lab – Group Activity) Score: ____________/30 Direction: Perform the following exploratory activities at home and write your observations and try to explain what happened Properties of liquid Observation (Group) What do you think is the reason for this? (Individual) 1. Surface tension What happened when the clip was Materials: plastic cups, water, paper placed ____? clip, dishwashing liquid 1. Water only Procedure _______________________  Fill the one cup with water up to the ___________________________ brim. ___________________________  Place the paper clip horizontally. 2. Water with Dishwashing liquid  Fill another cup with water up to the ___________________________ brim. ___________________________  Add several drops of dishwashing liquid.  Place the paper clip horizontally. 2. Viscosity How long before the glass was Materials: water, oil, plastic cup (2), emptied? plastic spoon, timer 1. Glass with oil Procedure __________________________  Place about one spoonful of oil in a ____________seconds cup.  Get the cup with oil. Set the timer. 2. Glass with water  Slowly tilt the glass at an angle to ____________seconds allow the oil to flow. Stop the timer as the glass is emptied.  Place about one spoonful of water in a cup.  Do the same with the cup containing water.  Compare the time it took for the glass with oil and the glass with water to be emptied. 3. Capillary action Describe what you see. Materials: pechay baguio water, Initially at the start of observation. red/green/blue food color, jar __________________________ Procedure: _______________________ __________________________  11 Colegio de los Baños – GENERAL CHEMISTRY 2 Properties of liquid Observation (Group) What do you think is the reason for this? (Individual)  Place about 250mL of water in a __________________________ jar. After 12 hours  Dissolve about 1/2 teaspoon of food __________________________ color in the water and stir. __________________________  Trim the bottom of the pechay __________________________ baguio leaf to straighten. __________________________  Put the leaves inside the jar and leave overnight.  Record observations. 4. Vapor Pressure How long before evaporation was Materials: acetone, water, rubbing complete? alcohol, 1peso coin (3pcs), dropper, timer Procedure:  Pick an area with direct sunlight Acetone :____________seconds (example: window sill). Rubbing alcohol:  Arrange the coins beside each ____________seconds other.  Place 2 drops of water on the first coin.  Place 2 drops of acetone on the other.  Observe and record the time it takes for the water and the acetone to evaporate. ASSIMILATION (Individual Activity) Score: ____________/10 POST LAB 1. Upon learning the unique properties of water, list down 5 ways on how you can conserve it in your own homes or communities. 2. What did you like about the activity?  Colegio de los Baños – GENERAL CHEMISTRY 2 12 Prerequisite Assessment A. Differentiate the states or phases of matter. B. Give examples (one for each type of intermolecular forces of attraction). Learning Materials: Module, pen, paper, chemistry books, internet (if applicable) Prerequisite Content-knowledge: States of matter Prerequisite Skill: Differentiate the physical changes that matter may undergo. INTRODUCTION: A. TIME ALLOTMENT: 4 hours B. CONSULTATION: For questions and clarifications, you may consult your subject teacher on the assigned schedule. C. RUA: At the end of the lesson, you should be able to:  Interpret the phase diagram of water and carbon dioxide  Determine and explain the heating and cooling curve of a substance. D. INSTITUTIONAL VALUES: Integrity, Excellence and Social Responsibility Learners will be able to apply critical thinking in:  Differentiating the phase changes  Identifying the different phases in the phase diagram given pressure and temperature  Interpreting the heating and cooling curve of a substance E. OVERVIEW OF THE LESSON This lesson is about how matter undergoes phase changes and how the phase diagrams depict these changes. This also introduces the energy accompanied by these changes through the heating and cooling curves. STUDENT’S EXPERIENTIAL LEARNING Individual Learning Chunk 1: Phase Changes Types of phase changes. The change from solid to liquid is melting, liquid to gas is vaporization, and solid to gas is sublimation. These changes take place when heat is absorbed (heat gained). They are endothermic processes. The reverse change from gas to liquid is condensation, gas to solid is deposition, and liquid to solid is freezing. These changes give off heat (heat lost) and are exothermic processes. 12  Colegio de los Baños – GENERAL CHEMISTRY 2 13 How does a change in energy affect phase changes? Phase changes occur when heat is added or removed from a substance. When a substance is heated, the added energy is used by the substance in either of two ways: a. The added heat increases the kinetic energy of the particles, and the particles move faster. The increase in kinetic energy is accompanied by an increase in temperature. b. The added heat is used to break attractive forces between particles. There is no observed increase in temperature when this happens. Often a change in the physical appearance of the substance is observed, such as a phase change. Conversely, the removal or release of heat results in two ways: a. A decrease in kinetic energy of the particles. The motion of the particles slow down. A decrease in temperature is observed. b. Forces of attraction are formed, and a phase change may occur. No change in temperature is observed. HEATING CURVE COOLING CURVE In both the heating and cooling curves, there are certain portions where the temperature changes as heat is being added or removed, and portions where the temperature remains constant even if heat is being added or removed. What is happening at these portions? 1. When heat change is accompanied by a change in temperature, a change in kinetic energies of the particles in the substance is occurring. The particles are either moving faster or slowing down. 2. When temperature remains constant during heat change, the particles move at the same speed. The heat added or removed is involved in breaking or forming attractive forces. A phase change occurs at this temperature: solid melts or liquid freezes at the melting point, which is also the freezing point; liquid boils, or gas condenses at the boiling point, which is also the condensation point. During phase changes, two physical states of the substance exist at the same time. When addition or removal of heat is stopped at this temperature, the two physical states will interconvert from one state to the other, and will be at equilibrium. 13  Colegio de los Baños – GENERAL CHEMISTRY 2 14 How much heat is required to convert 135 g of ice at −15 °C into water vapor at 120 °C? Solution The transition described involves the following steps: 1. Heat ice from −15 °C to 0 °C 2. Melt ice 3. Heat water from 0 °C to 100 °C 4. Boil water 5. Heat steam from 100 °C to 120 °C The heat needed to change the temperature of a given substance (with no change in phase) is: q = m × c × ΔT. The heat needed to induce a given change in phase is given by q = n × ΔH. Using these equations with the appropriate values for specific heat of ice, water, and steam, and enthalpies of fusion and vaporization, we have: 14  Colegio de los Baños – GENERAL CHEMISTRY 2 15 Chunk 2. Phase Diagrams  A phase diagram is a graphical representation of the physical states of a substance under different conditions of temperature and pressure.  It gives the possible combinations of pressure and temperature at which certain physical state or states a substance would be observed. Each substance has its own phase diagram. What are the features of a phase diagram?  Phase diagrams are plots of pressure (usually in atmospheres) versus temperature (usually in degrees Celsius or Kelvin).  The diagram is divided into three areas: solid, liquid and gaseous states. The boundary between the liquid and gaseous regions stop at point C, the critical temperature for the substance. A. Three Areas/Regions  The three areas are marked solid, liquid, and vapor. Under a set of conditions in the diagram, a substance can exist in a solid, liquid, or vapor (gas) phase. The labels on the graph represent the stable states of a system in equilibrium.  Suppose a pure substance is found at three different sets of conditions of temperature and pressure corresponding to A, B, and C as shown in the following diagram: B. Three Lines (Curves)  The lines that serve as boundaries between physical states represent the combinations of pressures and temperatures at which two phases can exist in equilibrium. In other words, these lines define phase change points.  The green line divides the solid and liquid phases, and represents melting (solid to liquid) and freezing (liquid to solid) points.  Melting (or freezing) curve – the curve on a phase diagram which represents the transition between liquid and solid states. It shows the effect of pressure on the melting point of the solid. Anywhere on this line, there is equilibrium between the solid and the liquid.  The blue line divides the liquid and gas phases, and represents vaporization (liquid to gas) and condensation (gas to liquid) points.  Vaporization (or condensation) curve – the curve on a phase diagram which represents the transition between gaseous and liquid states. It shows the effect of pressure on the boiling point of the liquid. Anywhere along this line, there will be equilibrium between the liquid and the vapor. 15  Colegio de los Baños – GENERAL CHEMISTRY 2 16  The red line divides the solid and gas phases, and represents sublimation (solid to gas) and deposition (gas to solid) points. C. Two Important Points  The triple point is the combination of pressure and temperature at which all three phases of matter are at equilibrium. It is the point on a phase diagram at which the three states of matter coexist. The lines that represent the conditions of solid-liquid, liquid-vapor, and solid- vapor equilibrium meet at the triple point. It is a unique combination of temperature and pressure where all three phases are in equilibrium together.  The critical point terminates the liquid/gas phase line. It is the set of temperature and pressure on a phase diagram where the liquid and gaseous phases of a substance merge together into a single phase. Beyond the temperature of the critical point, the merged single phase is known as a supercritical fluid. The temperature and pressure corresponding to this are known as the critical temperature and critical pressure. Based on the phase diagram of water :  At pt A. water exists both as solid & gas.  At pt B. water exists as liquid.  At pt C. water exists as gas.  At pt D. water exists as solid, liquid & gas. o triple point: (273.2 K, 0.006 atm)  At pt E. water exists both as liquid & gas. o critical point: (647 K, 1 atm) Phase diagram of water 16  Colegio de los Baños – GENERAL CHEMISTRY 2 17 Name: _______________________________________ Section: ________________ LAST NAME, FIRST NAME MIDDLE INITIAL ENABLING ASSESSMENT ACTIVITY 2 ENGAGEMENT (Think Pair Share) HEATING CURVE Score: ____________/15 A. Direction: Use the heating curve to the right to answer the following questions: (1pt each) 1. What is the melting point of the substance? ____ 2. What is the boiling point of the substance? ____ 3. Which letter represents heating of the solid? ____ 4. Which letter represents heating of the gas? ____ 5. Which letter represents melting of the solid? ____ 6. Which letter represents boiling of the liquid? ____ 7. At points b and d why doesn’t the temperature change even though heat energy is added? ____ B. Solve the following problems. Show your solution and box your final answer. 1. Calculate the energy necessary to melt 50 grams of ice (c=2.09 J/g oC) Heat of fusion (Hfusion) of water = 334 J/g. (3pts) Given: Solution: 2. How much energy is needed to raise the temperature of 250 grams of water from 25oC to its boiling point and then boil it? The specific heat of water is 4.18 J/g oC and the heat of vaporization is 2260 J/g. (5pts) Given: Solution: 17  Colegio de los Baños – GENERAL CHEMISTRY 2 18 ASSIMILATION (Individual Activity) PHASE DIAGRAM OF CARBON DIOXIDE Score: _____________/10 Consider the diagram below to identify the different points. Using the phase diagram for carbon dioxide shown above: A. Determine the state of CO2 at the following temperatures and pressures: 1. −30 °C and 2000 kPa: __________________ 2. −60 °C and 1000 kPa: __________________ 3. −60 °C and 100 kPa: __________________ 4. 20 °C and 1500 kPa: __________________ 5. 0 °C and 100 kPa: __________________ 6. 20 °C and 100 kPa: __________________ B. Fill in the blanks. 1. At the critical point( _____oC, ______kPa), CO2 exists as ____________. 2. At the triple point( _____oC, ______kPa), CO2 exists as ____________. 18  Colegio de los Baños – GENERAL CHEMISTRY 2 19 Prerequisite Assessment Prepare a solution by dissolving a teaspoonful of sugar in a glass half-filled with water. Stir the mixture well. Observe closely and keenly. Describe the appearance of the resulting material. What can be observed? Explain. Learning Materials: Module, pen, paper, chemistry books, internet (if applicable) Prerequisite Content-knowledge: States of matter and their macroscopic properties Prerequisite Skill: Differentiate the macroscopic properties of the states of matter INTRODUCTION: A. TIME ALLOTMENT: 4 hours B. CONSULTATION: For questions and clarifications, you may consult your subject teacher on the assigned schedule. C. RUA At the end of the lesson, you should be able to: Use different ways of expressing concentration of solutions: percent by mass, mole fraction, molarity, molality, percent by volume, percent by mass, ppm D. VALUES INTEGRATION: Integrity, Excellence and Social Responsibility Learners will be able to apply critical thinking in:  Identifying the intermolecular forces of attractions in solids and liquids and  Analyzing how chemical properties of solids such as melting point, boiling point, solubility and reactivity are affected by the dominant intermolecular forces present. E. OVERVIEW OF THE LESSON This lesson is about how solutions are expressed into different concentration measures. STUDENT’S EXPERIENTIAL LEARNING Individual Reading Chunk 1. Physical Properties of Solutions In the pre- assessment activity, the sugar is referred to as the solute and water is referred to as the solvent. The solute is the substance that is being dissolved, while the solvent is the dissolving medium. When one substance dissolves into another, a solution is formed. 19  Colegio de los Baños – GENERAL CHEMISTRY 2 20 Physical Properties of Solutions  In all solutions, whether gaseous, liquid, or solid, the substance present in the greatest amount is the solvent, and the substance or substances present in lesser amounts are the solute(s).  The solute does not have to be in the same physical state as the solvent, but the physical state of the solvent usually determines the state of the solution. As long as the solute and solvent combine to give a homogeneous solution, the solute is said to be soluble in the solvent.  Solutions are homogeneous mixtures of two or more substances whose components are uniformly distributed on a microscopic scale. The component present in the greatest amount is the solvent, and the components present in lesser amounts are the solute(s).  The formation of a solution from a solute and a solvent is a physical process, not a chemical one. Substances that are miscible, such as gases, form a single phase in all proportions when mixed. Substances that form separate phases are immiscible.  Solvation is the process in which solute particles are surrounded by solvent molecules. When the solvent is water, the process is called hydration.  The overall enthalpy change that accompanies the formation of a solution, ΔHsoln, is the sum of the enthalpy change for breaking the intermolecular interactions in both the solvent and the solute and the enthalpy change for the formation of new solute–solvent interactions.  Exothermic (ΔHsoln