Chapter 7: Electrochemistry

2. Paula is studying the rules for assigning oxidation states. She learns that the oxidation state of oxygen is usually -2, except in peroxides where it is -1. In H2O2, what is the oxidation state of oxygen?

3. Waleed is learning about oxidation and reduction in terms of electron transfer. He knows that a substance that loses electrons is oxidized. In the reaction: Fe + CuSO4 → FeSO4 + Cu, which substance loses electrons?

4. Rania is studying cathodic protection. She learns that cathodic protection involves making the metal the cathode to prevent corrosion. Which of the following uses cathodic protection?

5. Waleed is determining the oxidation number of an atom in a compound. He wants to find the oxidation state of chromium in K2Cr2O7. Given K is +1 and O is -2, what is the oxidation state of Cr?

6. Which of the following is an example of oxidation?

7. George is learning the rules for assigning oxidation states. He knows that the oxidation state of an element in its elemental form is zero. What is the oxidation state of chlorine in Cl2?

8. Samir is learning about the formula of ionic compounds. He knows that the formula must be electrically neutral. What is the formula of the ionic compound formed between sodium (Na+) and sulfate (SO4^2-)?

9. Omar is learning about coating with a thin layer of another metal. He understands that tinning is coating iron with tin. What is the purpose of tinning?

10. George is studying oxidation states of monoatomic ions. He knows that a monoatomic ion's oxidation state is its charge. What is the oxidation state of Ca2+?

11. Which metal is commonly used for sacrificial protection of iron?

12. Mohamed is learning about corrosion. He understands that corrosion can be prevented by cathodic protection. Which of the following structures commonly uses cathodic protection?

13. Tina is studying oxidation states of monoatomic ions. She knows that the oxidation state is equal to the ion's charge. What is the oxidation state of Al3+?

14. Which method prevents corrosion by coating iron with zinc?

15. Laura is studying the prevention of corrosion. She learns that painting is a common method. Which of the following is an advantage of using paint for corrosion prevention?

16. Xia is learning about oxidizing agents. She understands that an oxidizing agent is itself reduced. In the reaction: 2FeCl2 + Cl2 → 2FeCl3, which is the oxidizing agent?

17. Which of the following is NOT a method to prevent corrosion?

18. Samir is studying the prevention of corrosion by coating with a thin layer of another metal. He learns that galvanizing is one such method. What metal is used in galvanizing to coat iron?

19. Rania is learning about corrosion prevention methods. She learns that electroplating is used to coat a metal with a thin layer of another metal. Which of the following is an example of electroplating?

20. Which process converts electrical energy into chemical energy?

21. Corrosion mainly affects:

22. Bongani is learning about reducing agents. He understands that a reducing agent causes reduction of another substance and is itself oxidized. In the reaction: CuO + H2 → Cu + H2O, which is the reducing agent?

23. Bilal is learning about reduction in terms of gain of electrons. He understands that reduction involves the gain of electrons. Which of the following represents reduction?

24. Which of the following is an application of electrochemistry?

25. What is the oxidation state of Cl in NaCl?

26. The anode in a galvanic cell is:

27. Paula is studying galvanizing. She learns that galvanizing is the process of coating iron or steel with zinc. Why is zinc used in galvanizing?

28. In corrosion, iron acts as:

29. Yara is studying corrosion prevention methods. She learns that coating with paint is a simple and effective method. Which of the following is an advantage of painting to prevent corrosion?

30. Corrosion is an undesirable process because it: