PHYSICAL-SCIENCE-Q3-SLM8.pdf

Physical Science 11 Physical Science – Grade 11 Quarter 3 – Module 8: Intermolecular Forces and Properties of Substances First Edition, 2020 Republic Act 8293, Section 176 states that no copyright shall subsist in any work of the Government of the Philippines. However, prior appr...

Physical Science 11 Physical Science – Grade 11 Quarter 3 – Module 8: Intermolecular Forces and Properties of Substances First Edition, 2020 Republic Act 8293, Section 176 states that no copyright shall subsist in any work of the Government of the Philippines. However, prior approval of the government agency or office wherein the work is created shall be necessary for exploitation of such work for profit. Such agency or office may, among other things, impose as a condition the payment of royalties. Borrowed materials (i.e., songs, stories, poems, pictures, photos, brand names, trademarks, etc.) included in this module are owned by their respective copyright holders. Every effort has been exerted to locate and seek permission to use these materials from their respective copyright owners. The publisher and authors do not represent nor claim ownership over them. Published by the Department of Education - Schools Division of Pasig City Development Team of the Self-Learning Module Writer: Mark Cristopher C. Nilo Editor: Bernadette S. Agustin Reviewer: Bernadette S. Agustin Illustrator: Edison P. Clet Layout Artist: Micaelle Lauren V. Tenorio Management Team: Ma. Evalou Concepcion A. Agustin OIC-Schools Division Superintendent Carolina T. Revera, CESE OIC-Assistant Schools Division Superintendent Manuel A. Laguerta EdD OIC-Chief, Curriculum Implementation Division Education Program Supervisors Librada L. Agon EdD (EPP/TLE/TVL/TVE) Liza A. Alvarez (Science/STEM/SSP) Bernard R. Balitao (AP/HUMSS) Joselito E. Calios (English/SPFL/GAS) Norlyn D. Conde EdD (MAPEH/SPA/SPS/HOPE/A&D/Sports) Wilma Q. Del Rosario (LRMS/ADM) Ma. Teresita E. Herrera EdD (Filipino/GAS/Piling Larang) Perlita M. Ignacio PhD (EsP) Printed in the Philippines by Department of Education – Schools Division of Pasig City  Physical Science 11 Quarter 3 Self-Learning Module 8 Intermolecular Forces and Properties of Substances Introductory Message For the Facilitator: Welcome to the Physical Science Grade 11 Module 8 on Intermolecular Forces of Attraction and Properties of Substances! This Self-Learning Module was collaboratively designed, developed and reviewed by educators from the Schools Division Office of Pasig City headed by its Officer-in-Charge Schools Division Superintendent, Ma. Evalou Concepcion A. Agustin, in partnership with the City Government of Pasig through its mayor, Honorable Victor Ma. Regis N. Sotto. The writers utilized the standards set by the K to 12 Curriculum using the Most Essential Learning Competencies (MELC) in developing this instructional resource. This learning material hopes to engage the learners in guided and independent learning activities at their own pace and time. Further, this also aims to help learners acquire the needed 21st century skills especially the 5 Cs, namely: Communication, Collaboration, Creativity, Critical Thinking, and Character while taking into consideration their needs and circumstances. In addition to the material in the main text, you will also see this box in the body of the module: Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners. As a facilitator you are expected to orient the learners on how to use this module. You also need to keep track of the learners' progress while allowing them to manage their own learning. Moreover, you are expected to encourage and assist the learners as they do the tasks included in the module. For the Learner: Welcome to the Physical Science Grade 11 Module 8 on Intermolecular Forces and Properties of Substances! The hand is one of the most symbolized part of the human body. It is often used to depict skill, action and purpose. Through our hands we may learn, create and accomplish. Hence, the hand in this learning resource signifies that you as a learner is capable and empowered to successfully achieve the relevant competencies and skills at your own pace and time. Your academic success lies in your own hands! This module was designed to provide you with fun and meaningful opportunities for guided and independent learning at your own pace and time. You will be enabled to process the contents of the learning material while being an active learner. This module has the following parts and corresponding icons: Expectation - These are what you will be able to know after completing the lessons in the module Pre-test - This will measure your prior knowledge and the concepts to be mastered throughout the lesson. Recap - This section will measure what learnings and skills that you understand from the previous lesson. Lesson- This section will discuss the topic for this module. Activities - This is a set of activities you will perform. Wrap Up- This section summarizes the concepts and applications of the lessons. Valuing-this part will check the integration of values in the learning competency. Post-test - This will measure how much you have learned from the entire module. Ito po ang parts ng module  EXPECTATIONS After going through this module, it is assumed that you will be able to: 1. explain how intermolecular forces correlate with the phases of matter; 2. interpret trends between intermolecular forces and physical properties; and 3. recognize practical applications of intermolecular forces. PRETEST 1. Which of the following has the strongest intermolecular forces of attraction? a. carbon dioxide, CO2 c. hydrogen chloride, HCl b. ammonia, NH3 d. water, H2O 2. Arrange the following substances based on increasing boiling point. w. ethane, C2H6 x. carbon dioxide, CO2 y. isopropyl alcohol, C3H8O y. carbon tetrachloride, CCl4 a. w, x, z, y c. y, w, z, x b. x, y, w, z d. y, z, x, w 3. Both substances A and B are made up of nonpolar molecules, but A has a greater size and mass than B. Which of the following statements is true about both substances? a. A has a stronger london dispersion forces than B b. B has a stronger london dispersion forces than A c. neither A nor B exhibits london dispersion forces. d. both A and B exhibits london dispersion forces of the same strength 5. Which of the following statements would best explain why water exhibits a relatively higher boiling point compared to other substances? I. Water is a polar substance. II. The interaction between the partially positive hydrogen end and partially negative end oxygen accounts among water molecules accounts for some of its relatively high boiling point. a. I only b. II only c. I and II d. none of the above  Fig. 1. Source: https://openstax.org/books/chemistry-atoms-first-2e/pages/10-1-intermolecular-forces 4. Based on the graph, which of the following element in the Carbon family that formed a compound with hydrogen has the highest boiling point? A. silane, SiH4 B. methane, CH4 C. stannane, SnH4 D. germane, GeH4 RECAP Last time, you have enjoyed our discussion about intermolecular forces. Can you still remember the different types of intermolecular forces? If so, then join me in classifying these substances based on their intermolecular forces. 1. NH3 2. PCl5 3. CH4 4. CO2 5. O2 6. H2 7. H2O 8. NaCl & H2O 9. CaO 10. CO London Dipole – Dipole Hydrogen Bonds Ion – Dipole Dispersion Interactions Interactions Forces LESSON What makes solid, liquid, and gas molecules in such forms? Why substances have the phase they are in? What happens to alcohol when exposed to air? How is it possible to solidify and liquefy gases? What about a bag of water in the freezer overnight? Well, these are basic phases and the transitions in a matter that are observable around us even at home. You can examine under certain situations, that liquids may exhibit viscosity, a resistance to flow naturally. Water as liquid may also develop a “skin” on its surface, as observed in liquid droplets and light objects resting on its surface. On the other hand, solids cannot be expected to flow due to its rigidity as affected by stronger intermolecular forces between its molecules.  Moreover, certain conditions allow substances to transform and alter from one form to another. But, the rate on how they change from one phase to another as well as how they mix with other substances are governed largely by the strength that attracts their molecules together against the forces within the particles. In Practical Chemistry, for a substance to be useful, one has to alter the phase of matter so it could be combined with other substances under physical or chemical reaction. Or let alone, merely changing phase could make certain substances more useful, even without combining with other substances. In a condensed state (solid or liquid), it is expected that the strength of intermolecular force (IMF) is greater than in an uncondensed form (gaseous), where kinetic energy is higher or faster. The IMF in a molecule has to be broken for a transition to take place. With strong IMF and low energy within molecules, substance tends to be in solid or liquid form. On the contrary, with high energy within molecules, matter tends to be in gaseous form. The magnitude of energy is mostly determined by the temperature establishing a stable phase under certain conditions. Let us examine further the link between the physical properties like boiling point and melting point, to strengths of intermolecular forces. London Dispersion Force Strength and Molecular Mass Oxygen, hydrogen, and nitrogen are diatomic molecules without permanent dipoles when existing independently. Their high kinetic energy causes intermolecular forces between them very weak. This weak and temporary force you learned from module I, refers to London Dispersion Forces (LDF) and is the only force present in these atmospheric gaseous molecules (at room temperature). Although London dispersion forces are relatively weak, they become very significant when molecules and atoms are very close. As atoms and molecules get bigger and heavier, the strength of London dispersion between them increases. In other words, the strength of London dispersion forces is stronger with increasing molecular mass as well as its melting and boiling point. Dipole-Dipole Interactions, Its Strength Against LDF On the other hand, the effect of dipole – dipole attraction is significant when we compare the properties of a polar molecule against a non-polar molecule. Take hydrogen chloride (HCl), and nonpolar molecule fluorine (F2) as examples. If they will be subjected at a temperature of 150 K, molecules of both substances would have the same average kinetic energy (KE). Halogen Molar Mass Melting Point Boiling Point Phase fluorine, F2 38 g/mol 53 K 85 K gas hydrogen chloride, HCl 36.46 g/mol 158.9 K 188.1 K liquid Table 1. Melting and Boiling Points of Fluorine (F2) and Hydrogen chloride (HCl) It can be deduced that the strength of dipole-dipole attractions between HCl molecules is greater compared to the attractions between nonpolar F2 molecules. The former exhibits a higher normal boiling point of 188 K compared to 85 K to that of the latter. Thus, in terms of IMF and boiling point, HCl > F2. Exceptional Hydrogen Bond A special dipole – dipole interaction between molecules happens when hydrogen interacts to a highly electronegative atom such as nitrogen, oxygen and fluorine. The polar molecule with such hydrogen and electronegative atom would have the strongest van der Waals forces, called hydrogen bond. Though not as strong as a covalent bond and not a real bond itself, H-bond is strong enough to influence the physical properties of molecules. Water in particular exhibits hydrogen bond and consists of polar molecules. Because of its polarity, water displays some distinctive properties uncommon to most substances. High surface tension, high boiling point, and low density, are the unique physical properties of water that set it apart from other molecules. The hydrogen bond between water molecules are evenly pulled at all sides in any vessel. While on its surface, water molecules are pulled inwards, creating the so-called surface tension. This allows small insects and light objects to walk and remain on its surface respectively. Hydrogen bonding also plays a significant role in the structure and function of several and most biological molecules particularly in nucleic acids and proteins. 1. Hydrogen bonds induce the DNA to form a helical structure. Fig.1. Source: http://book.bionumbers.org/what-is-the-energy-of-a-hydrogen-bond/ 2. H-bonds in proteins of long chains of amino acids. Fig. 2. Source: http://book.bionumbers.org/what-is-the-energy-of-a-hydrogen-bond  ACTIVITIES Objective: To look for trends among intermolecular forces and properties of specific molecules Activity 1 : “Non-negotiable Mass Rule” Materials: pen and paper, periodic table of elements (optional) Procedure: Below is a random record of the observed properties of certain halogens. Arrange the following in increasing order and answer the questions that follow: Halogen Molar Mass Atomic Radius Melting Point Boiling Point astatine, At2 420 g/mol 150 pm 575 K 610 K bromine, Br2 160 g/mol 114 pm 266 K 332 K chlorine, Cl2 71 g/mol 99 pm 172 K 238 K iodine, I2 254 g/mol 133 pm 387 K 457 K fluorine, F2 38 g/mol 72 pm 53 K 85 K Table 2. Melting and Boiling Points of the Halogens Source: https://opentextbc.ca/chemistry/chapter/10-1- intermolecular-forces/ Questions: 1. Which molecule has the greatest mass and atomic size? 2. Which molecule has the lowest boiling point and melting point? 3. Which has the strongest London dispersion force (LDF)? 4. How does the molar mass, of each given diatomic halogen molecule, relates to their melting and boiling points? Choose the best word to make each statement correct: 5. From the above given table, as the molar mass of a molecule in halogens (increases, decreases) the melting point and the boiling point of the substance also (increases, decreases). 6. In the same way, as atomic size (increases, decreases) so is the (K.E., LDF). In van der Waals dispersion forces, 7. boiling point is (higher, lower) for larger compounds 8. melting point is (higher, lower) for larger compounds 9. freezing point is (higher, lower) for smaller compounds (inference) 10. vapor pressure is (higher, lower) for smaller compounds (inference) Activity 2: “What’s in a Dipole to Beat It All?” Halogen Molar Mass Melting Point Boiling Point Phase fluorine, F2 38 g/mol 53 K 85 K gas hydrogen chloride, HCl 36.46 g/mol 158.9 K 188.1 K liquid Table 3. Melting and Boiling Points of Fluorine (F2) and Hydrogen chloride (HCl) Procedure: The following are inferences drawn from the given data above. Unscramble the jumbled letters to reveal the correct word in each statement. 1. Fluorine and hydrogen chloride are both dicotmia molecules. 2. The two samples above have almost the same molecular sams. 3. Fluorine has London Dispersion force because it is rlonpoan molecule. 4. Hydrogen chloride has dipole-dipole interactions because it is lopra molecule. 5. HCl2 is iluqid at 188 K, intermolecular force caused them to ‘stick together’. 6. Fluorine is ags at 85 K, intermolecular force cannot keep molecules together. Activity 3: “Amazing H-Bond” Procedure: Compare the strength of the hydrogen bonds to the strength of other dipole – dipole interactions. Study the graph below and answer the questions. Figure 3. Boiling points of Group 14 (Carbon Family), Group 15 (Oxygen Family), Group 16 (Nitrogen Family), and Group 17 (Fluorine Family) Source: https://villanovachemistry.wordpress.com/chemical-bonding/ Questions: 1. What can you say about the trend of boiling point of the hydrides of Group 14 as you go down the group from CH4 to SnH4? 2. Are these substances polar or nonpolar? 3. What force exists in these molecules? 4. What can you say about the trend of the intermolecular force in this group? 5. What can you say about the molecular mass of these compounds? 6. What can you say about the boiling point of the hydride of the first element of each group of 15, 16 and 17? 7. What can you say about the trend of molecular mass among NH3, H2O and HF? 8. What predominant bond exists in these compounds? 9. Which has the highest boiling point among the three? 10. Is the relationship higher mass, higher boiling point, true with water?  WRAP-UP The type of intermolecular forces that exist between atoms of molecules and some ions significantly influence the physical properties of substances. Generally, the degree of increasing strength of intermolecular forces is as follows: London Dispersion Forces (LDF), Dipole – Dipole Interactions (DDI) and lastly, Hydrogen Bonding (HB). Additionally, all molecules however, possess the slightest attraction which is LDF, and would vary depending on the polarity. Substances that are nonpolar and exhibit London Dispersion Forces commonly exists in gaseous and liquid forms. They have considerably low boiling point compared to other substances. Water on the other hand, exhibits special properties such as high boiling point, high surface tension, and high density. These are all attributed to hydrogen bonds present in water molecules- one of the vital molecules of living things. It is important to note that, hydrogen bonds play a crucial role in maintaining configurations and shapes of important biomolecules such as nucleic acids and proteins. Molecules that constitute a wide range of compounds in three basic forms are fashioned based on the strength of force connecting each other by the so-called Intermolecular Forces. Similarly, their distinctive properties especially their behaviour to external forces are dictated and influenced by the Intermolecular Forces (IMF) that hold the molecular design and unique characteristics of compounds distinct from one another. VALUING Observe the things around you. Some materials may be of the same phase or state, but still possess unique properties and characteristics that make them unique from one another. In effect, different materials react and behave in varied ways to external forces. The same holds true when they combine with other molecules. What is your reflection on this? How does this relate to how people build relationships? ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________.  POSTTEST 1. Which of the following has the weakest intermolecular forces of attraction? a. carbon dioxide, CO2 c. hydrogen chloride, HCl b. ammonia, NH3 d. water, H2O 2. Arrange the following substances based on increasing boiling point. methane, CH4 hydrogen fluoride, HF ammonia, NH3 water, H2O a. ammonia, NH3, hydrogen fluoride, HF, methane, CH4, water, H2O b. methane, CH4, ammonia, NH3, hydrogen fluoride, HF, water, H2O c. ammonia, NH3, methane, CH4, hydrogen fluoride, HF, water, H2O d. water, H2O, methane, CH4, ammonia, NH3, hydrogen fluoride, HF 3. Both substances Y and Z are liquid, but Y exhibits hydrogen bonds while Z exhibits London dispersion forces. How will the two differ in terms of their boiling point? a. Y will tend to have higher boiling point than Z b. Z will tend to have higher boiling point than Y c. Neither A nor B will boil at a certain temperature. d. The boiling point of the two substances will be the same. 4. Based on the graph, which of the following element in the Carbon family that formed a compound with hydrogen has the lowest boiling point? a. silane, SiH4 C. stannane, SnH4 b. methane, CH4 d. germane, GeH4  POSTTEST 1 A. Carbon dioxide, CO2 2 B. methane, CH4, ammonia, NH3, hydrogen fluoride, HF, water, H2O 3. A. Y will tend to have higher boiling point than Z 4. B. methane, CH4 5. C. I and II ACTIVITY 3 1. increasing 3. LDF 5. increasing 7. decreasing 9. water 2. nonpolar 4. increasing 6. increasing 8. H-bond 10. no ACTIVITY 2 1. diatomic 2. mass 3. nonpolar 4. polar 5. liquid 6. gas ACTY. 1 1. astatine 3. astatine 5. Increases /increases 7. higher 9.lower 2. fluorine 4. Directly related 6. Increases/ LDF 8. higher 10. lower ACTIVITY 1 Halogen Molar Mass Atomic Radius Melting Point Boiling Point fluorine, F2 38 g/mol 72 pm 53 K 85 K chlorine, Cl2 71 g/mol 99 pm 172 K 238 K bromine, Br2 160 g/mol 114 pm 266 K 332 K iodine, I2 254 g/mol 133 pm 387 K 457 K astatine, At2 420 g/mol 150 pm 575 K 610 K Table 4. Melting and Boiling Points of the Halogens Source: https://opentextbc.ca/chemistry/chapter/10-1- intermolecular-forces/ PRETEST 1) d 2) a. w, x, z, y 3) A > (LDF) B 4) c. II and III 5) Stannane, SnH4 KEY TO CORRECTION d. none of the above c. I and II b. II only a. I only relatively high boiling point. negative end oxygen accounts among water molecules accounts for some of its II. The interaction between the partially positive hydrogen end and partially I. Water is a polar substance. relatively higher boiling point compared to other substances? 5. Which of the following statements would best explain why water exhibits a  References Bayo - ang, Roly B., Maria Lourdes G. Coronacion, Annamae T. Jorda, Anna Jamille Restubog, and Maria Noemi M. Moncada. Physical Science. Quezon City, Philippines: Educational Resources Corporation, 2016. Chapter 111 Intermolecular Forces. Pearson Education, Inc., 2012. https://www2.chemistry.msu.edu/courses/cem151/Intramolecularforces_Ch11.pd f. Dapul , Gian Karlo R., Clarisa C. Avila, and Johnrob Y. Bantang. Teaching Guide for Senior High School Physical Science. Edited by Nathaniel P. Hermosa. Quezon City, Philippines: Commission on Higher Education, 2016.