An exam for an Advanced Chemistry unit on Redox. and Electrochemical processes.
2 points
2
Question 1
1.
Oxidation numbers tell us:
2 points
2
Question 2
2.
A voltaic cell has an anode and a cathode. How do electrons act in relation to these two electrodes?
2 points
2
Question 3
3.
Which of the following metals would be the cathode, thereby losing electrons to all the other metals in the group?
2 points
2
Question 4
4.
Check all the changes here that are using an electrochemical process to create electricity:
2 points
2
Question 5
5.
Check all the changes here that are using electricity to cause a chemical reaction:
2 points
2
Question 6
6.
Check all the changes here that are spontaneous redox. reactions:
2 points
2
Question 7
7.
In this compound the oxidation number of chlorine is:
2 points
2
Question 8
8.
The oxidation number of nitrogen in this ion is:
2 points
2
Question 9
9.
An electrochemical cell, like a common flashlight battery becomes "dead" when:
2 points
2
Question 10
10.
Rechargeable batteries:
2 points
2
Question 11
11.
I can make an electrochemical cell at home. I need:
2 points
2
Question 12
12.
Zn + HgO → ZnO2-2 + Hg
Look at this redox. reaction and determine what gets oxidized and what gets reduced. Select all that apply:
2 points
2
Question 13
13.
2Fe2O3 + 3C → 4Fe + 3CO2
Look at this redox. reaction and determine what gets oxidized and what gets reduced. Select all that apply:
2 points
2
Question 14
14.
2Ag+1 + 2NO3-1 + Cu → Cu+2 + 2NO3-1 + 2Ag
Look at this redox. reaction and determine what gets oxidized and what gets reduced. Select all that apply:
2 points
2
Question 15
15.
Using the half reaction reference sheet in your workbook determine the theoretical potential of the following cell: Ba|Ba+2 || Pt+2|Pt
2 points
2
Question 16
16.
Using the half reaction reference sheet in your workbook determine the theoretical potential of the following cell: Mg|Mg+2 || Cd+2|Cd
2 points
2
Question 17
17.
Using the half reaction reference sheet in your workbook determine the theoretical potential of the following cell: Au|Au+1 || Cr+3|Cr
2 points
2
Question 18
18.
In the reaction H2 + O2 -------> H2O hydrogen gets:
8 points
8
Question 19
19.
Balance the redox. reaction above using the half reaction method. Show your work.
8 points
8
Question 20
20.
Balance the redox. reaction above using the half reaction method. Show your work.
8 points
8
Question 21
21.
Draw an electrochemical chemical cell containing the metals calcium (Ca, Ca+2) and platinum (Pt,Pt+2) with potassium nitrate (KNO3 : potassium and nitrate ions dissociated) in the salt bridge. Use your reduction potential chart to determine which metal gets oxidized and which one gets reduced. Assume the solutions in each half cell are nitrates of the metals. Label the following:
a. Cathode and anode (1 point)
b. Direction of current flow (1 point)
c. Positive pole and negative pole (1 point)
d. Direction of nitrate ion flow through the salt bridge (1 point)
e. Direction of potassium ion flow in the salt bridge (1 point)
f. Which electrode gains and which loses mass (1 point)
g. The theoretical voltage reading on the voltmeter in the system (2 pts)