Question

What is number of moles of electron passed when a current of \(2\) Amp flows through solution of electrolyte for \(10\) minutes?

• A. \(1.784\times 10^{-2}\)
• B. \(1.243\times 10^{-2}\)
• C. \(2.022\times 10^{-2}\)
• D. \(8.041\times 10^{-2}\)

Hint:

Charge = current times time; divide by the Faraday constant.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
One mole of electrons carries a charge of 1 faraday, \(F = 96500\) C.

Step 2: Find the Charge:
\(t = 10 \times 60 = 600\) s.
\[ Q = It = 2 \times 600 = 1200\ \text{C} \]

Step 3: Moles of Electrons:
\[ n = \frac{Q}{F} = \frac{1200}{96500} = 1.243\times 10^{-2}\ \text{mol} \]

Step 4: Check the Other Options:
\(1.784\times10^{-2}\) would need 1722 C, \(2.022\times10^{-2}\) would need 1951 C, \(8.041\times10^{-2}\) would need 7760 C. None matches 1200 C. So (B) is correct.

Final Answer:
About \(1.243\times10^{-2}\) mol of electrons pass, option (B). \[ \boxed{\text{(B) } 1.243\times 10^{-2}} \]