Question

During the electrolysis of molten sodium chloride, the time required to produce $0.10$ mol of chlorine gas using a current of $3$ amperes is

• A. 55 minutes
• B. 110 minutes
• C. 220 minutes
• D. 330 minutes

Answer 1

The Correct Option is B

To determine the time required to produce 0.10 mol of chlorine gas during the electrolysis of molten sodium chloride using a current of 3 amperes, we can use Faraday's laws of electrolysis. The relevant laws and calculations involved include:

1. Determine the chemical reaction: During the electrolysis of molten sodium chloride, chlorine gas is produced at the anode. The half-reaction for chlorine at the anode is: 2Cl^- \rightarrow Cl_2(g) + 2e^-\
2. Calculate the amount of charge needed: According to the half-reaction, 2 moles of electrons are required to produce 1 mole of chlorine gas. Hence, to produce 0.10 mol of chlorine gas, we need 0.20 mol of electrons.
3. Calculate the total charge: 1 mole of electrons corresponds to a charge of F = 96500 coulombs (Faraday constant). Therefore, the charge needed is: Q = 0.20 \times 96500 = 19300 coulombs
4. Use the formula Q = I \times t to find the time:
   • Q = 19300 coulombs
   • I = 3 amperes
   • Rearrange to find time: t = \frac{Q}{I} = \frac{19300}{3} \approx 6433.33 seconds
5. Convert time from seconds to minutes: As there are 60 seconds in a minute, t \approx \frac{6433.33}{60} \approx 107.22 minutes, which is approximately 110 minutes.

Thus, the correct answer is 110 minutes.

This confirms the provided answer and rules out other options based on clear calculations using Faraday’s laws.