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Chemistry Quiz #3 Name: _________________ Place the correct answer in the space provided on the bottom of the page 7. After a reaction involving lithium, the lithium ion will be a. Li+ c. Li+2 b. Li d. Li-2 PART A: MULTIPLE CHOICE 1. Bonds created by the sharing of electrons are a. Hydrogen Bonds c. Ionic Bonds b. Covalent Bonds d. Metallic Bonds 8. How many covalent bonds are in H2O a. 1 c. 3 b. 2 d. 4 2. Which of the following is an ionic bond? a. CO2 c. MgO b. H2O d. SO 9. The covalent bond in a nitrogen molecule N2 will be a. single bonded c. triple bonded b. double bonded d. quadruple bonded 3. Which element will gain electron(s) in an ionic bond? a. calcium c. sodium b. potassium d. oxygen PART B: TRUE/FALSE – Enter T for true, F for false 4. What kind of atoms form covalent bonds a. two non-metals c. a metal and a non-metal b. two metals d. noble gases 10. A double bond occurs when two electrons are shared between two atoms. False – four electrons shared 5. What is the combining capacity of sulfur a. 1 c. 7 b. 2 d. 8 11. Oxygen can only form covalent bonds. False - both 12. Dissolving an ionic compound in water will separate it. True 6. Which of the following is responsible for bonding in an atom a. protons c. electrons b. neutrons d. any of the above 1 ______ 2 ______ 3 ______ 4 ______ 5 ______ 6 ______ 7 ______ 8 ______ 9 ______ 10 ______ 11 ______ 12 ______ Part C: APPLICATION 13. Determine the missing information: (4) Name of compound chemical formula cation Combining capacity of cation anion Combining capacity of anion Aluminum Selenide Al2S3 Al3+ 3 Se2- 2 Berylium Iodide BeI2 Be2+ 2 I- 1 14.Draw a Bohr-Rutherford model of oxygen O2 (3) 15.Draw the structure diagram of methane CH4 (1) Part D: COMMUNICATION 16. Is an ionic compound likely to form between Oxygen and Sulfur? Explain your reasoning. (3) No, both are non-metals. Ionic compounds require one atom to give electrons away (a metal) and one atom to receive electrons (a non-metals). That cannot happen here as both atoms are non-metal and tend to gain electrons in an ionic bond. Oxygen and Sulfur will end up sharing electrons and will form a covalent bond 17. Explain why Potassium (K) cannot become an anion. (3) Anion is a negatively charged ion, but K is a cation when it becomes an ion. K is a metal and only has one valence electron in its outer shell. It is therefore likely to lose that electron to obtain an outer shell. When an electron is lost, a positively charged ion is created, referred to as a cation. 18. Is Neon likely to form either an ionic bond or covalent bond? Explain your reasoning. (3) Neon is a noble gas and has a full outer shell. It is therefore satisfied and does not need to lose, gain or share any electrons. It will therefore form neither an ionic nor covalent bond. Part E: THINKING 19. Zinc phosphide, Zn3P2, is often used as a rat poison. Phosphorus has 5 valence electrons. How many valence electrons does each zinc atom lose? Justify your answer. (3) If P has 5 valence electron, it needs to gain 3 electrons to fill its outer shell. Since there are 2 P atoms, then it needs to gain 2*3=6 electrons. This is also the number of electrons that the Zinc atoms need to give away. Given there are 3 Zn atoms, it needs to give away 6 electrons in total, then each Zn electron will give away 6/3=2 electrons. Each zinc atom will give away 2 electrons.