Ch & 12 Test. Name: Class: Date: Multiple Choice Identify the choice that best completes the statement or answers the question.

Transcription

1 Name: Class: Date: Ch & 12 Test Multiple Choice Identify the choice that best completes the statement or answers the question. 1. How many valence electrons does Argon, a noble gas, have? a. 1 b. 4 c. 6 d When an atom loses an electron, it becomes a a. positive ion. b. negative ion. c. neutral ion. d. neutral atom. 3. Magnesium bromide is an ionic compound with the chemical formula MgBr 2. What does the 2 tell you? a. Bromide has a 2- charge. b. There are two magnesium ions to every bromide ion. c. There are two bromide ions for every magnesium ion. d. Bromide has a 2+ charge. 4. In the chemical formula for an ionic compound, which item is written first? a. the name of the positive ion b. the name of the negative ion c. the subscripts d. the charges 5. The chemical name for the compound with the formula Na 2 S is a. sodium fluoride. b. magnesium sulfide. c. lithium oxide. d. sodium sulfide. 6. An ionic bond is the attraction between a. similarly charged ions. b. oppositely charged ions. c. neutral ions. d. neutral atoms. 7. A mixture made of two or more elements, at least one of which is a metal is called a(n) a. superconductor. b. metallic bond. c. complex metal. d. alloy. 1

2 Name: 8. A chemical bond formed when two atoms share electrons is called a(n) a. ionic bond. b. covalent bond. c. metallic bond. d. polyatomic bond. 9. Which of the following properties is not determined by the structure of metal atoms and the bonding between their valence electrons? a. luster b. mass c. ductility d. thermal conductivity 10. Which is a property shared by most molecular compounds? a. high boiling point b. high melting point c. low melting point d. nonpolar bonds 11. Which of the following is a property of ionic compounds? a. They have low melting points. b. They have low boiling points. c. They form hard, brittle crystals. d. They contain no charged particles. 12. Which is a characteristic property of acids? a. They turn blue litmus paper red. b. They turn red litmus paper blue. c. They taste bitter. d. They do not react with metals. 13. Which of the following statements about acids is true? a. Acids have a ph greater than 7. b. Acids corrode platinum and gold and have a bitter taste. c. Acids have a slippery feel and turn red litmus paper blue. d. Acids have a sour taste and turn blue litmus paper red. 14. A chemical reaction that absorbs energy in the form of heat is described as a. endothermic. b. exothermic. c. combustion. d. unbalanced. 15. CaCO 3 represents a chemical a. symbol. b. formula. c. subscript. d. reaction. 2

3 Name: 16. The substances listed on the left side of a chemical equation are the a. products. b. coefficients. c. precipitates. d. reactants. 17. In chemical reactions, what does the principle of conservation of mass mean? a. Matter is not created or destroyed. b. The total mass of the reactants is greater than the total mass of the products. c. The total mass of the reactants is less than the total mass of the products. d. Matter is not changed. 18. Which of the following is a balanced equation? a. 4 Na + O 2 2 Na 2 O b. 2 Na + O 2 2 NaO 2 c. Na 2 O + O 2 2 NaO d. Na 2 + O Na 2 O The minimum amount of energy needed to start a reaction is the a. exothermic energy. b. endothermic energy. c. activation energy. d. chemical energy. 20. A material used to decrease the rate of a chemical reaction is a(n) a. inhibitor. b. catalyst. c. enzyme. d. fuel. 21. Increasing the temperature of a chemical reaction a. speeds up the reaction rate. b. does not affect the reaction rate. c. increases the concentration of the reactants. d. makes the reactant particles slow down. 3

4 Name: Short Answer 22. In an electron dot diagram of aluminum (Al), how many dots should be drawn around the element s symbol? Why? 23. What color would litmus paper turn in a solution of baking soda? Explain your answer in terms of ph. 4

5 Name: 24. If the products formed from the burning candle are mostly carbon (C), carbon dioxide (CO 2 ), and water (H 2 O), what elements were in the reactants? How do you know? 25. Write a balanced equation for the reaction above and identify what type of chemical reaction is taking place.. 5

6 Name: 26. Extra Credit!!! 8 points 1. Find the error in the equation and correct it so the equation is correctly balanced: 2. Name each of the compounds: the OH- group is known as hydroxide 3. Identify the type of chemical reaction that is taking place. AlCl 3 + NaOH NaCl 3 + AlOH. 6