Science Quarter 2 Module 2 PDF

Department of Education 9 National Capital Region SCHOOLS DIVISION OFFICE MARIKINA CITY Science Quarter 2 -Module 2 Properties of Ionic and Covalent Compounds Jordan B. Plopino...

Department of Education 9 National Capital Region SCHOOLS DIVISION OFFICE MARIKINA CITY Science Quarter 2 -Module 2 Properties of Ionic and Covalent Compounds Jordan B. Plopino 1 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  What I Need to Know You have learned from the previous lessons that all elements have their own distinctive characteristics among others. These elements become more useful when they combine to form compounds and complex molecules. This module will help you learn and explore more about various compounds classified as ionic compounds and covalent compounds. The module is divided into three lessons, namely:  Lesson 1 – Naming of Ionic and Covalent Compounds  Lesson 2 – Physical Properties of Ionic and Covalent Compounds  Lesson 3 – Application of the Properties of Ionic and Covalent Compounds in Natural Phenomena After going through this module, you are expected to recognize different types of compounds (ionic or covalent) based on their properties such as melting point, hardness, polarity, and electrical and thermal conductivity. S9MT-IIb-14 Specifically, you should be able to:  identify and describe ionic and covalent compounds based on their chemical formula and chemical names;  enumerate and discuss different physical properties of ionic and covalent compounds;  distinguish ionic from covalent compounds based on their physical properties; and  cite natural phenomena that uses different physical properties of ionic and covalent compounds (ex. Snowflakes, voltaic cells) What I Know Read each question carefully and encircle the letter of the correct answer. 1. Covalent and ionic bonding produce certain types of compounds that have different properties. What is the general term used for all the compounds with covalent bond? A. atom C. molecule B. compound D. none of the choices 1 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE 2. Electrical and thermal conductivity is one of the properties of compounds. Which of the following types of bond will have a high electrical conductivity? A. non-polar covalent bond C. covalent bond B. ionic bond D. polar covalent bond 3. The following compounds are commonly found in nature or in our household. Which do you think will have the highest melting/boiling point if we are to subject those substances to heating? A. sucrose (sugar) C. sodium chloride (NaCl) B. dihydrogen monoxide (water) D. oxygen gas 4. What happens to the electron of metal element in ionic bonding forming a compound? A. shared to a non-metal C. shared unequally with non-metal B. transferred to non-metal D. none of the choices 5. Non-polar covalent bonding involves the equal sharing of electrons between atoms to attain stability. Which of the following compounds will have non-polar covalent bonding? A. CH4 B. HCl C. NaCl D. O2 6. What do we call to a type of covalent bond wherein electrons are shared unequally between atoms? A. ionic C. non-polar covalent B. polar covalent D. chemical bond 7. Which is of the following physical properties is TRUE to an ionic compound? A. low melting point C. high melting point B. low boiling point D. poor conductor 8. What is the term used to indicate the representative unit of ionic compounds? A. molecule B. formula unit C. atom D. ionic bond 9. How do you call the bonding between a metal and a non-metal to form a compound? A. ionic bond C. non-polar covalent bond B. covalent bond D. polar covalent bond 10. Which is the main reason why electron(s) of metal element tend(s) to transfer completely to non-metal element? A. metals have higher melting point B. non-metals have low melting point C. metals have lower electronegativity value D. metals have higher electronegativity value 2 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE Lesson The Ionic and Covalent Compounds 1 In this lesson, you will be exploring the different examples of ionic and covalent compounds with its chemical formula and corresponding names. The different activities were carefully chosen and prepared for you to easily familiarize both the chemical names and formula of various compounds that are naturally- occurring or those that are made in laboratory. What’s In Complete the table by writing the correct word or value on the space provided. Use the periodic table of elements as your guide. On a separate sheet of paper, copy the table then write your answers on it. Name of the Symbol of the Family Number Metal/Non- Element Element metal/metalloid Calcium 1. IIA 2. 3. Na 4. Metal Oxygen 5. 6. 7. 8. P VA 9. The symbols, names, family number and classification of these elements are of great importance in understanding how to assign names and chemical formula to all compounds and identify as to which classification they belong. What’s New You Can Do It! Try to guess the missing element (symbol) or name of compound on the following items. Use the Periodic Table of Elements as your guide. 3 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  Take a closer look on the figures used for each element. Note that the cloud figure has a non-metal element while the circle figure encloses a metal element. The following compounds formed above can be classified into two types: ionic compounds or covalent compounds. Which of the following combination of elements belong to ionic compound or covalent compound? What Is It If we talk about chemical bonding, a lot of things should be considered. There is a need to know first the major classification of elements: Metals, Metalloids, or Non-Metals. Assigning the names of compounds, guided by the chemical formula, is a lot easier than classifying them as to ionic or covalent compounds. Every bit of matter, compounds, or molecules existing in nature or artificially prepared are governed by these special bonds or attractive forces: ionic bond and covalent bond. Why do atoms behave this way? How do we define these bonds? Ionic bond is formed between two ions by the complete transfer of electrons. This usually happens between a metal and non-metal. In this case, metals lose electron(s) and are completely transferred to non-metal to attain stability. This happens due to a higher electronegativity value of non-metals compared to metal elements. The ions formed also have specific names. The element (metal) that lose electron becomes positively charged thus it is called a cation. The element (non-metal) that gain electron becomes negatively charged and is called an anion. As shown in the illustration, sodium (Na) as metal tends to lose an electron and was gained by chlorine (Cl) which is a non-metal forming sodium chloride (table salt), a stable compound. The resulting compound in ionic bonding can be called a formula unit. 4 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE Okay! I will..well, you must! I will give off and take and accept your transfer my electron for us to electron. e become STABLE. Na Cl Sodium chloride (NaCl) Let’s look and study the table below: Chemical formula Cation Anion Chemical Name MgO Mg 2+ O 2- Magnesium oxide CaS Ca 2+ S 2- Calcium sulfide KBr K 1+ Br 1- Potassium bromide CaF2 Ca 2+ F 1- Calcium fluoride Covalent bond, on the other hand, is formed by the sharing of electrons. In this case, two non-metals are involved in the formation of bond to obtain stability. This type of bond exists in all diatomic molecules. The compound formed by a covalent bond is commonly called a molecule. Diatomic molecules include oxygen gas (O 2), hydrogen gas (H2), fluorine gas (F2), etc. Although electrons are shared under covalent bond, sometimes the sharing is not equal. This will lead to a more specific type of such bond. When there is unequal sharing of electron(s), the bond is called a polar covalent bond. In the case of equal sharing of electrons, it is then called a non-polar covalent bond. Let’s look and study the illustration below. Now, we share..oh yes! But for now, it’s electrons huh!?And unequal sharing because then we will I have greater force to become STABLE. let that electron stay closer to me. e H Cl Hydrogen chloride (HCl) Hydrogen (H) atom forms covalent bond with chlorine to produce hydrogen chloride or hydrochloric acid. But in this case, there is an unequal sharing of electrons wherein, as shown in the illustration, chlorine has stronger pull than that of hydrogen taking electron closer to its side. Thus, this type of bond falls 5 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE under a polar covalent bond. The most common example of a polar molecule is water (H2O). Let’s observe what happens in the next illustration. Finally! Care..and then to share achieve EQUALLY! STABILITY! e H H Hydrogen gas (H2) Two hydrogen (H) atoms form a covalent bond to produce hydrogen gas, which is a diatomic molecule. In this case, the two atoms exhibit equal sharing of electrons thus it is classified as a non-polar covalent bond. As mentioned earlier, diatomic molecules are considered to have non-polar covalent bonds. What’s More Activity 1.1: Is It Ionic or Covalent? Objectives: 1. Write the correct name of compounds based on their chemical formula. 2. Identify the ionic and covalent compounds. What you need: Periodic table of Elements, pen, separate sheet for your answer. What to do: Complete the table by writing the correct name of the compound guided by the chemical formula. Put a check ( ⁄ ) on the column where to classify the compound: ionic, polar covalent, or non-polar covalent. Write your answers on the space provided. Chemical Covalent Formula Chemical name Ionic Polar Non-polar Ex. BaO Barium oxide / 1. CaF2 2. Cl2 3. HF 4. Li2S 5. HI 6 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE Guide Questions: 1. What kind of elements mainly comprise ionic compounds? ______________ How about the covalent compounds? ___________________________________ 2. In the case of ionic bond where there is complete transfer of electron, what kind of element gives off or donate electron? ___________________________ How about the kind of element that gains electron? ____________________ 3. How would you differentiate ionic from covalent compounds? _______________________________________________________________________________ _______________________________________________________________________________ What I Have Learned Activity 1.2: It’s a-MAZE-ing Ionic and Covalent Journey Trace the maze guided by the concepts learned in the lesson on ionic and covalent compounds. Use a crayon (single color) to color and trace the sequence of concepts from the starting point to finish. 7 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  What I Can Do Let’s Write A Single Paragraph! Give your own idea on the following situations or issues. Write one paragraph with at least 5 sentences using the learned concepts. Make sure that you will include the science terms used in the lesson and a SIMPLE TITLE. (note: Choose only ONE ITEM) 1. Why do you think almost all elements need to bond with other elements and form a compound? Would it make these elements more usable in the industry by forming compounds? Can you mention some of its application or use in technology, business or manufacturing? 2. Our world is facing global medical issue which is the Covid-19 pandemic. Considering all these science concepts (ionic and covalent compounds), can you cite some of its practical application in health and in medical field? Your work will be rated with the following criteria. Criteria Excellent Good Needs Improvement Mechanics and No errors in punctuation, Minor errors in Many errors in Grammar capitalization, spelling punctuation, punctuation, and grammar capitalization, spelling capitalization, spelling construction and grammar and grammar construction construction Organization Main idea and many Main idea and some Main idea and few (Topic and related details are related details are related details are Supporting clearly stated. stated. stated. Sentence) Title: ________________________ ___________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________. Assessment Read each question carefully and encircle the letter of the correct answer. 1. What do we call the general term used for compounds formed with covalent bond? A. compound B. element C. formula unit D. molecule 8 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE 2. Which of the following statements that suits the description about covalent compound? A. It always involves metal and non-metal elements. B. It occurs when there is a sharing of electrons between elements. C. It is formed by the complete transfer of electrons between elements. D. All are TRUE to a covalent compound. 3. What is the term used to mean the compound that results from ionic bonding? A. compound B. element C. formula unit D. molecule 4. Which of the following compounds has a of non-polar covalent bond? A. acids B. calcium oxide C. hydrogen chloride D. oxygen gas 5. Which of the following is the type of bond that results when elements equally share electrons? A. covalent bond C. polar covalent bond B. ionic bond D. non-polar covalent bond Additional Activities IONIC AND COVALENT COMPOUND: A Concept Map Supply the following boxes with correct science words to complete the flow chart/concept map. This serves as a summary of the most important concepts or details from the discussion. Remember all the concepts learned from the lesson. 9 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE Lesson The Physical Properties of Ionic and 2 Covalent Compounds What’s In COMPLETION OF PARAGRAPH! Recall all the concepts learned from the first lesson. Then, supply the blanks with the correct missing science term(s) to complete the thought of the paragraph. (Note: No duplication of word/s in each item) Compounds Ionic Metal Polar Shared Molecules Non-metal Non-polar Transfer Stable Most of the common elements in nature need to bond with other elements and form (1)___________. This bonding allows them to become (2)__________ and be in a more usable form. The two types of bond that exists in nature are (3)_________ and covalent bond. Ionic bonding involves non-metal and a (4)________, wherein there is a complete (5)________ of electron(s). In the case of covalent bonding, the element involved is (6)_________ and then electron(s) is(are) (7)______. When electrons are shared equally between atoms, it is called (8)_________. As for the case of unequal sharing of electrons, it is then called (9)_________. All compounds formed by covalent bonding is generally called (10)____________. What’s New Guess what specific word best fits with the set of photos presented on each item. 10 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  What Is It There are so many compounds existing in nature, and some are prepared in a laboratory setting. Scientists devised so many ways on how these substances can be grouped or classified. This lesson will focus on the two kinds of compounds: ionic and covalent. Aside from the molecular structure or composition, they can also be classified by considering their physical properties. So, let us explore the physical properties of ionic and covalent compounds to fully understand how they differ from one another. Basically, all matter can exist in 3 common states: solid, liquid, or gas. Ionic compounds generally exist in a solid form. They can be characterized with crystalline (crystals) form like sodium chloride (table salt). As with covalent compounds, they cover a wider scope because these compounds can exist in 3 states of matter. Ionic compounds have very high melting and boiling points as compared to covalent compounds. Wax, as an example of covalent compound, melts easily unlike salt. But salt easily dissolve in water compared to wax that is completely insoluble. This pertains to the solubility property of compounds. Mostly, ionic compounds are hard but brittle while covalent compound tend to have soft texture. Lastly, ionic compounds are good conductor of electricity because they form ions, most especially when dissolved in water. Covalent compounds, normally, do not conduct electricity and are generally referred to as poor conductors. As you can see in figure 1, salt and sugar are used to test the electrical conductivity of ionic and covalent compound respectively. Naturally, water itself can conduct electricity but with the addition of salt in it, it makes the LED light brighter. Addition of sugar, on the other set up, does not improve the conductivity of water. Salt as an example of ionic compound, is a good conductor of electricity than sugar which is a covalent compound. Figure 1. Improvised electrical conductivity set-up. 11 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  What’s More Activity 2.1: Salty vs Waxy! Objective: Recognize the physical properties of ionic and covalent compounds using common household materials. What you need: salt, sugar, candle wax, water, 3 small cups, 3 metal spoons, 3 pcs. ¼ bond paper, candle and lighter. What to do: 1. Place the 3 sheets of bond paper on a flat surface separately. Put the salt on the first sheet, a small amount of candle wax on the second sheet, and lastly a small amount of sugar on the third sheet. 2. Using separate spoon, crush or press the samples and observe. 3. Using the three separate cups, put water on it (half-filled). 4. Place the crushed salt, candle wax, and sugar on each cup separately. Stir using the spoon, then observe. Note: For procedure #5, please perform it with adult supervision because a lighted candle will be used. 5. Place a small amount of each substance on separate metal spoons. Lit the candle and heat the substance, then observe what happens. 6. Record your observations and gathered data on the table. Solubility Crystal Substance/Material It Melts Hardness (Dissolves in structure (YES or NO) water – YES (Yes/No) or NO) Sodium chloride (NaCl) – table salt candle wax (C25H52) Table sugar (C12H22O11) Guide Questions: 1. Based from the experiment and data gathered, which substance is an ionic compound? ____________________How about the covalent compound? ______________ 2. How do ionic compounds differ from covalent compounds in terms of properties._______________________________________________________________________ 12 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  What I Have Learned Complete the table. Correctly identify the physical properties of ionic and covalent compound by putting a check (/) mark on the column provided. Comparison of the Physical Properties Between Ionic and Covalent Compounds. Physical Properties Ionic Covalent State/Structure Solid, liquid, gas Mostly solid/forms crystals Melting/Boiling Low points High Hardness Soft, brittle Hard Solubility in water Mostly dissolves in water Mostly does not dissolve in water Conductivity Good conductor Poor conductor Aside from the contrasting properties of the two types of compounds, there are other characteristics that are somehow true to both. This will include the following: solid state, crystal formation etc., but this has still some considerations. The only fact that these compounds have in common is that they both form bonds between atoms. What I Can Do ON A SEARCH MISSION: HOUSEHOLD MATERIALS Before proceeding to your special mission inside your house, take note of the following: 1. Make sure that you are supervised by your parent or guardian while performing the task. 2. Use household materials that are not corrosive or dangerous to handle. Your Mission! Aside from the materials used in the experiment (salt and candle wax), choose 4 common household materials found at your home. Be sure to have 2 samples for each type of compound (2 for ionic and 2 for covalent). 13 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  Look for the label of the material (if there is) or research for its chemical composition. Make a table for the summary of your data gathered. Follow the format below. Common Name Chemical Name Chemical formula Classification Ex. Sugar Sucrose C12H22O11 Covalent compound Assessment Read each question carefully and encircle the letter of the correct answer. 1. Which of the following is a correct property of an ionic compound? A. It always exists as solid C. It is a poor conductor of electricity B. It can be brittle and forms crystal D. It may exist as solid, liquid and gas 2. Some covalent compounds are solid and form crystals like ionic compounds. Which of the following is an example of covalent compound that forms crystals? A. salt B. sugar C. wax D. all of the choices 3. All are properties of covalent compound EXCEPT? A. low melting point C. can be solid, liquid or gas B. good conductor of electricity D. mostly does not dissolve in water 4. Which of the following compounds can form ions when dissolved in water making it a good conductor of electricity. A. coffee B. powdered juice C. salt D. sugar 5. Which of the following is NOT a property of an ionic compound? A. mostly does not dissolve in water C. mostly forms crystals B. with high melting point D. good conductor of electricity Additional Activities Compare and Contrast! Make a Venn diagram to compare ionic and covalent compounds. Consider all the concepts learned from the two lessons. Do not only focus on their 14 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE physical properties. Please include its compositions and the nature of bonding. In a Venn diagram, the center part of the overlapping two circles is where you put the concept or characteristic that is true to both. IONIC COVALENT Application of the Properties of Ionic Lesson and Covalent Compounds in Natural 3 Phenomena What’s In Write IC if the description refers to property of ionic compound or CC for property of covalent compound. ___ 1. It usually forms crystals or in solid form at room temperature. ___ 2. It has a low boiling and melting point. ___ 3. It can exist in solid, liquid, or gas. ___ 4. It is formed between a metal and non-metal elements. ___ 5. It easily dissolves in water and becomes good conductor of electricity. 15 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  What’s New Observe the following images. Identify, as many as you can, ionic or covalent compounds present on each image. Name the natural processes being shown on the illustrations. A. B. NaCl, H2O, Cl2, F2, Br2, MgCl2, KCl FIGURE 1 FIGURE 2 https://bit.ly/3qIUhjK https://bit.ly/2VWbloc A. B. Natural Process: ________________ Natural Process: __________________ Compounds present: ____________ Compounds present: ______________ What Is It There are many processes happening in nature that involves the presence of various compounds. Many of which help in maintaining life and the natural systems or cycles in the planet. To name a few natural phenomena, we can have the most common geologic cycle on earth, the hydrologic or water cycle. Aside from that, we can also mention the most vital life-sustaining process which is the photosynthesis. Hydrologic or water cycle involves three stages namely: evaporation, condensation, and precipitation as shown in fig. 1. The highlight on this process is the presence of water molecules, a polar covalent compound. In the ocean, sodium chloride or salt is also present, an ionic compound. But in the entire cycle, salt is left behind during evaporation turning water molecule into vapor (gas) from its liquid state. In the next process, many compounds are also involved. This is referred to as the food-processing among autotrophs or producers, the photosynthesis. Going back to fig. 2, it shows a simple process of photosynthesis. Carbon dioxide and water, both covalent compounds, are used by plants’ chloroplasts together with 16 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE sunlight to produce oxygen and glucose. Oxygen (O2) is in the gas state that supports so many life forms on earth. What’s More Activity 3.1: Compounds in the Natural World Objective: Identify natural phenomena that involves ionic and covalent compounds and its properties. What to do: Observe and analyze the illustrations and answer the succeeding questions to fully understand what is shown in the image. 1. The image shows a wide area, which is near a lake or sea, where there are “concentrating ponds” that serve as basin for sea water. a. What do you think is the main product/compound being made on the scenario? ______________________________________________ b. What is the natural process involved to make the said product/compound? _________________ c. How are you going to classify the compound produced? Ionic or covalent? _________________ FIGURE 3. Salt Making d. What do you call the solid structure formed https://bit.ly/3oBRVkO by the product you answered in letter (a.)? ______________________________________________ e. Give at least two physical properties of compound you have identified. ____________________________________________________________________________ 2. The two images show snow and hail stones. Although Philippines has not yet experienced a snow fall, we already witnessed hail stones that come along with rainfall at some in time almost every year. You can go back to the previous images used for you to answer the following questions: FIGURE 4. Snow Packed Trees FIGURE 5. Large Hail Stones https://bit.ly/2VXQr8n https://bit.ly/3n5IARM 17 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  a. What do you think is the main reason for the formation of snow? __________ b. What do you call the natural process wherein snowflakes fall (like a rainfall) on the earth’s surface? _______________________________________________________ c. How would you classify snow/snowflakes? Ionic or covalent? _______________ d. What physical property can you mention that can be observed in snow/snowflake? _________________________________________________________ What I Have Learned There are several natural phenomena that involve the presence of ionic and covalent compounds as well as their physical properties. Complete the sentences below by supplying the correct word/s from the box.  Hydrologic or water cycle involves the presence (1.)________ which is the most polar compound in the planet.  (2.)___________ is referred to as the “food making” of plants or producers. Sunlight together with water and (3.)_______ are all processed or synthesized to produce glucose and (4.)________ gas. All the raw materials and by products as the result of the process are all classified as covalent bonds.  Seawater can be placed in a certain basin to be exposed to sunlight and let the water molecules evaporate then leave (5.)_____ crystals behind. These crystals are classified as ionic compound.  Snow refers to frozen (6.)______ molecules forming ice crystals that results from below freezing point temperature.  Since snow is just composed of water molecule, it is then considered as covalent bond. This only shows that covalent compound can exists in three Carbon dioxide water oxygen salt photosynthesis states of matter: solid, liquid, and gas. What I Can Do Read carefully and answer the succeeding questions. Metro Manila is the busiest and most populated region in the country. With this, there is a greater chance for the different types of pollution to occur in the place. Let us the air pollution. Air pollution results where there is a large presence of solid and liquid particles and certain types of gases suspended in the air. These 18 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE gases and particles came from vehicles, factories, and other human-made activities. It involves the following substances namely: carbon monoxide, carbon dioxide, lead, nitrogen dioxide, ozone, sulfur dioxide and other gases. The pandemic brought by the COVID-19 virus forced the entire country to take action to limit its spread by implementing total lockdown. Metro Manila, with the greatest number of cases, was put to Enhanced Community Quarantine (ECQ) to alleviate the widespread of the virus. This, somehow, brought a positive result in as much as air pollution is concerned. Since transportation through public utility vehicles is strictly prohibited, the release of certain gases in the air that causes pollution is also minimized. Guide Questions: 1. What are some examples of gases or particles that cause air pollution? ___________________________________________________________________________ 2. How would classify those gases or particles? Ionic or Covalent? _____________ 3. What do you think is the best way to, at least, lessen the air pollution in metropolitan Manila? _____________________________________________________ C Assessment Read each question carefully and encircle the letter of the correct answer. 1. Which is the main reason for the formation of snow in some places? A. precipitation C. very low temperature B. formation of clouds D. evaporation 2. Which of the following is the natural process for the formation of salt crystals? A. condensation C. precipitation B. evaporation D. none of the choices 3. It is the most common compound that completes the hydrologic cycle which is continuously happening in the planet. A. carbon dioxide B. oxygen gas C. salt D. water 4. It is a covalent compound which is the result or product of photosynthesis aside from oxygen gas. A. carbon dioxide B. glucose C. nutrients D. water 5. What do you call the crystals left behind when seawater evaporates? A. impurities C. snowflakes B. salt D. none of the choices 19 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  Additional Activities WORD SEARCH! Encircle 5 science terms/words which are related in this module that are hidden on the puzzle grid. The words maybe hidden in any direction. Posttest Read each question carefully and encircle the letter of the correct answer. 1. Hydrogen gas (H2) and oxygen gas (02) are called diatomic molecules. All these types of molecules belong to what type of covalent bond? A. covalent B. ionic C. polar D. non-polar 2. Electrical and thermal conductivity is one of the properties of compounds. Which of the following types of chemical bond will have a high electrical conductivity? A. covalent bond C. non-polar covalent bond B. ionic bond D. polar covalent bond 3. In covalent bonding, electrons are shared between atoms or elements to attain stability. What do you call the particle/substance produced with covalent bond? A. atom C. compound B. molecule D. none of the choices 4. Which is of the following physical properties is TRUE to an ionic compound? A. low melting point C. poor conductor B. low boiling point D. high melting point 20 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE 5. The following compounds are commonly found in nature or in our household. Which of the following will have the highest melting temperature? A. sucrose (sugar) C. oxygen gas B. dihydrogen monoxide (water) D. sodium chloride (NaCl) 6. Non-polar covalent bonding involves the equal sharing of electrons between atoms to attain stability. Which of the following compounds has a non-polar covalent bond? A. HCl B. CH4 C. O2 D. NaCl 7. Which is TRUE to a compound with polar covalent bond? A. electron is transferred C. electron is shared equally B. electron is shared unequally D. electron is removed in an atom 8. What happens to the electron of metal element in ionic bonding forming a compound? A. shared to a non-metal C. shared unequally with non-metal B. transferred to non-metal D. none of the choices 9. What is the main goal of an element to bond with other elements and form a compound? A. to be reactive C. to be stable B. to be highly unstable D. to be unstable and stable 10. Which is the main reason why electron(s) of metal element tend(s) to transfer completely to non-metal element? A. metals have higher melting point B. non-metals have low melting point C. metals have higher electronegativity value D. metals have lower electronegativity value 21 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  References Anne Marie Helmenstine, Ph.D. “What Are Ionic and Covalent Compounds?” ThoughtCo. Accessed July 21, 2020. https://www.thoughtco.com/ionic-and- covalent-compounds-properties-3975966. “Covalent Bond Examples.” Math. Accessed July 21, 2020. https://www.softschools.com/examples/science/covalent_bond_examples/48 0/. “How Do Snowflakes Form? Get the Science behind Snow.” How do snowflakes form? Get the science behind snow | National Oceanic and Atmospheric Administration. Accessed July 21, 2020. https://www.noaa.gov/stories/how- do-snowflakes-form-science-behind-snow. Mott, Vallerie. “Introduction to Chemistry.” Lumen. Accessed July 21, 2020. https://courses.lumenlearning.com/introchem/chapter/comparison- between-covalent-and-ionic-compounds/. “National Snow and Ice Data Center.” How Snow Forms | National Snow and Ice Data Center. Accessed July 21, 2020. https://nsidc.org/cryosphere/snow/science/formation.html. “Sodium Ascorbate.” Accessed July 21, 2020. https://pubchem.ncbi.nlm.nih.gov/compound/Sodium-ascorbate. Sodium Chloride-NaCl-Salt of the Earth. Accessed July 21, 2020. https://chlorine.americanchemistry.com/Science-Center/Chlorine- Compound-of-the-Month-Library/Sodium-Chloride-NaCl-Salt-of-the-Earth/. Tears, Thomas. “Blank Venn Diagram - Circle , Free Transparent Clipart - ClipartKey.” clipartkey.com. Accessed July 21, 2020. https://www.clipartkey.com/view/iRwJxx_blank-venn-diagram-circle/. ———. “Know the Difference Between Ionic and Covalent Bonds.” ThoughtCo. Accessed July 21, 2020. https://www.thoughtco.com/ionic-and-covalent- chemical-bond-differences-606097. 22 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE  DISCIPLINE GOOD TASTE EXCELLENCE City of Good Character 23 What I have learned What’s More What’s In 1. water A. 1. IC 4. IC 2. photosynthesis a. salt 2. CC 5. IC 3. carbon dioxide b. evaporation 3. CC 4. oxygen c. ionic 5. salt d. crystals What’s New 6. water e. hardness, solubility A. Water cycle; crystal form/solid water, salt, water What I can do vapor/droplets 1. carbon dioxide, carbon B. monoxide, nitrous oxide, a. low temperature, B. Photosynthesis; sulfur dioxide freezing point CO2, O2, water, and glucose 2. covalent compounds b. precipitation 3. Minimize the use or c. covalent Assessment privately owned cars. Shift d. crystal form, 1. c 4. b to battery operated from liquid to solid 2. b 5. b motorcycles. Factories must 3. d take into consideration the best way to manage their Lesson 3 What’s New What’s In Assessment 1. melting 1. compound 1. b 2. crystals 2. stable 2. b 3. hardness 3. ionic 3. b 4. boiling 4. metal 4. c 5. transfer 5. a What’s more 6. non-metal 1. salt – ionic 7. shared Wax – covalent 8. non-polar 2. No. Some covalent compounds like 9. polar sugar can exist in crystals 10. molecules Lesson 2 What’s More! What’s In 1. Calcium fluoride; ionic 1. Ca 2. Chlorine gas; non-polar 2. Metal 6. VIA 3. Hydrogen fluoride; polar 3. Sodium 7. Non-metal 4. Lithium sulfide; ionic 4. IA 8. Phosphorus 5. hydrogen iodide; polar 5. O 9. Non-metal Guide Questions: What’s New 1. metals and non-metals; 1. Chlorine (Cl) Non-metals 2. Magnesium oxide 2. Metals; 3. Hydrogen fluoride Non-metal 4. Oxygen (O) 3. ionic compound is formed by the transfer 5. Hydrogen (H) of electrons while a covalent compound is Assessment formed when electrons are shared between 1. d 4.d atoms. 2. b 5. d 3. c Lesson 1 Answer Key  Development Team of the Module Writer: Jordan B. Plopino Content Editors: Jessica S. Mateo Jenalyn M. Salonga Robert J. Gaviola Rizalyn S. Santos Language Editors: Kristine Joyce G. Montejo Michelle I. Podadera Reviewers: PNU External Validators Cover Illustrators: Arriane Joy F. Isorena LR Librarian: Catherine C. Paningbatan Layout Artists: Keith Angeline N. Alejandro Jemwel Dela Paz Management Team: Sheryll T. Gayola Assistant Schools Division Superintendent OIC, Office of the Schools Division Superintendent Elisa O. Cerveza Chief, CID OIC, Office of the Assistant Schools Division Superintendent Jessica S. Mateo EPS-Science Ivy Coney A. Gamatero EPS – LRMS For inquiries or feedback, please write or call: Schools Division Office- Marikina City Email Address: [email protected] 191 Shoe Ave., Sta. Elena, Marikina City, 1800, Philippines Telefax: (02) 682-2472 / 682-3989 24 City of Good Character DISCIPLINE GOOD TASTE EXCELLENCE