Electrolysis Quantitative Aspects

What is Faraday's first law of electrolysis?

• The amount of electricity is inversely proportional to the chemical change

• Chemical change is not affected by the quantity of electricity

• The electrolyte does not play a role in the process

• Amount of chemical change is proportional to the quantity of electricity passed through the electrolyte.

Calculate the charge (in coulombs) required to deposit 0.5 moles of aluminum from Al3+ ions.

• 4339.3275 coulombs

• 4339327.5 coulombs

• 433932.75 coulombs

• 500000.25 coulombs

How is the current related to the time taken for electrolysis?

• The current is inversely proportional to the time taken for electrolysis.

• The current has no relation to the time taken for electrolysis.

• The current is proportional to the square of the time taken for electrolysis.

• The current is directly proportional to the time taken for electrolysis.

Explain how molar mass can be determined using electrolysis.

• By measuring the color change during electrolysis

• By counting the number of bubbles produced

• By electrolyzing a known quantity of the compound, measuring the electricity passed, and applying Faraday's laws.

• By analyzing the smell of the compound after electrolysis

Write the electrode reactions for the electrolysis of water.

• Anode: 2H2O(l) -> H2(g) + 2OH-(aq); Cathode: 2H2O(l) -> O2(g) + 4H+(aq) + 4e-

• Anode: 2H2O(l) -> O2(g) + 4H+(aq) + 4e-; Cathode: 2H2O(l) + 2e- -> H2(g) + 2OH-(aq)

• Anode: 2H2O(l) -> 2H2(g) + O2(g); Cathode: 2H2O(l) -> 2H2(g) + O2(g)

• Anode: 2H2O(l) -> 2H2(g) + O2(g); Cathode: 2H2O(l) -> H2(g) + 2OH-(aq)

What is Faraday's second law of electrolysis?

• Amount of chemical change is directly proportional to the quantity of electricity passed.

• The chemical change is proportional to the square of the quantity of electricity passed

• The quantity of electricity passed has no effect on the chemical change

• The amount of electricity passed is inversely proportional to the chemical change

If a current of 2A is passed through a solution for 3 hours, how many coulombs of charge are transferred?

• 30000 C

• 21600 C

• 25000 C

• 18000 C

What is the relationship between the amount of substance deposited and the quantity of electricity passed?

• Exponential

• No relationship

• Directly proportional

• Indirectly proportional

Calculate the mass of copper deposited when a current of 0.5A is passed through a CuSO4 solution for 2 hours.

• 0.63 grams

• 0.25 grams

• 0.42 grams

• 1.05 grams

What is the purpose of using inert electrodes in electrolysis?

• To ensure that the reactions at the electrodes are solely due to the passage of electrons through the external circuit.

• To speed up the electrolysis process

• To prevent the formation of gases during electrolysis

• To increase the conductivity of the electrolyte