1. 1. Give the oxidation number for the indicated element S in H 2 S 2 O 7 A)4 B)3 C)6 D)-4 E)-6

2. 2. What is the oxidation number of Cl in ClO 3 - A)4 B)5 C)1 D)-1 E) none of the above

3. 3. In which of the following compounds does oxygen not have an oxidation number of -2? A) H 2 O B) H 3 O C) H 2 O 2 D) OH -

4. 4. Electrochemistry is the study of…. A) converting chemical energy to electrical energy B) converting electrical energy to chemical energy C) converting electrical energy to thermal energy D) converting potential energy to kinetic energy E) both A and B

5. 5. What is a redox reaction? A) a reaction where one element is reduced and one is oxidized B) where elements disappear C) a way to cook food D) there is no such thing

6. 6. What is the oxidation number of Cl in HClO 4? A)1 B) 4 C) -3 D) 7 E) 0

7. 7. Which element is reduced? Au(NO 3 ) 3 +3Ag  AgNO 3 +Au A) Au B) Ag C) O D) N

8. 8. How can you tell if the equation is an oxidation or reduction? A) Oxidation loses an e -, reduction gains an e - B) Oxidation gains an e -, reduction loses an e - C) No change D) there is no product

9. 9. What is the oxidation number of C in Al(HCO 3 ) 3 ? A) +4 B) +3 C) +2 D) -4

10. 10. What is the oxidized element in this reaction C+H 2 O  CO+H 2 A) O B) C C) H D) 2

11. 11. What is the reducing agent in the following reaction KCl+H 2 SO 4  KHSO 4 +HCl A) KCl B) H 2 SO 4

12. 12.What is the sum of the oxidation numbers of all the elements in the compound arsenate (AsO 4 3- ) A) 5+ B) -11 C) -3 D) 3

13. 13. In a redox reaction the oxidation agent…. A) loses an e - B) gains an e - C) causes an element to lose an e - D) causes an element to gain an e -

14. 14. Zn+Cu 2+  Zn 2+ +Cu This reaction is A) not a redox reaction B) a redox reaction C) unbalanced and not a redox reaction D) unbalanced redox reaction

15. 15. Oxidation is… A) when an element gains an e - B) when an element loses an e - C) a decrease in the oxidaton number D) when an oxygen atom is added to a compound

16. 16. S+O 2 2-  SO 2 +4e - is the ____ half-reaction A) Oxidation B) reduction

17. 17. Oxidation number for Mn in KMnO4? A) 1 B) -2 C) 4 D) 0