THE ANSWER OF ELECTROLYSIS CELL QUIZ Part I

1.When group I metal salts in solution are electrolyzed, hydrogen gas is produced at the cathode, rather than the free metal. This is because ….
Answer : water is more easily reduced than group I metal ions in solution
2.The correct statement about electrolysis is ….
Answer : the cathode is negative, attract cations and is where reduction takes place
3.In the electrolysis of molten sodium chloride what are the products?
Answer : sodium at the cathode and chlorine at the anode
4.Identify the INCORRECTstatement in the following:
Answer : the cathode is the site of oxidation in an electrochemical cell.
5.How many grams of Ag(s) could be plated out on the cathode of an electrolytic cell by the passage of 20.0 Amps of current through AgNO3 solution for 30 minutes? Faraday's number = 96485 Coul/mol.
Answer (40.3 g)
6.Indium (In) can exist in solution as a couple of different ionic species. Suppose a 2.00 Amp current applied for 500.0 seconds produced 0.397 grams of In(s). What oxidation state is the indium in this solution?
Answer (+3)
7.How many coulombs are provided by a current of 1.00 x 104 A used in the commercial production of sodium in a 8.0 hour period?
Answer (2.9 x 107)
8.How many coulombs are used in the electrodeposition of gold by a current of 30.0 mA for 55 minutes?
Answer (99)
9.How many coulombs are provided by a current of 6.6 x 104 A used in the commercial production of lithium in a 12 hour period?
Answer (2.9 x 1011)
10.Passage of a current for 318 seconds through a silver coulometer results in the deposition of 0.640 g of silver. What is the amperage?
Answer (1.80)
11.Passage of a current for 437 seconds through a silver coulometer results in the deposition of 0.742 g of silver. What is the amperage?
Answer (1.52)
12.Passage of a current for 348 seconds through a silver coulometer results in the deposition of 0.498 g of silver. What is the amperage?
Answer (1.28)
13.An acidic solution containing the BiO+ ion is electrolyzed using a current of 0.750 A. How many grams of Bi plate out in 30.0 min? (Ar: Bi = 209)
Answer (0.97)
14.Beryllium occurs naturally in the form of beryl. The metal is produced from its ore by electrolysis after the ore has been converted to the oxide and then to the chloride. How many grams of Be(s) is deposited from a BeCl2 solution by a current of 5.0 A that flows for 1.0 h? (Ar: Be = 9)
Answer (0.84)
15.A proposed battery involves the reaction of Zn(s) and Cl2 (g) to give ZnCl2. If the battery is to deliver 1.5 A for 25 hours, what mass (g) of zinc must the anode contain? (Ar: Zn = 65.4)
Answer (460)
16.Electrolysis can be used to determine atomic masses. A current of 0.450 A deposits 0.786 g of a certain metal in 50.0 minutes. Calculate the atomic mass of the metal if n = 2.
Answer (112)
17.Electrolysis can be used to determine atomic masses. A current of 0.550 A deposits 0.358 g of a certain metal in 45.0 minutes. Calculate the atomic mass of the metal if n = 3.
Answer (70)
18.Electrolysis can be used to determine atomic masses. A current of 0.600 A deposits 2.38 g of a certain metal in exactly 1.00 hour. Calculate the atomic mass of the metal if n = 1.
Answer (106)
19.How many minutes will it take to plate out 5.00 g of Fe from an Fe(NO3)3 solution by a current of 1.50 A? (Ar: Fe = 56)
Answer (288)