JEE Mains · Chemistry · STD 12 - 2. Electrochemistry

A dilute solution of sulphuric acid is electrolysed using a current of \(0.10 \,A\) for \(2\, hours\) to produce hydrogen and oxygen gas. The total volume of gases produced at \(STP\) is \(......\,cm ^{3}\). (Nearest integer) \(\lfloor\) Given : Faraday constant \(F=96500 \,C\) \(mol^{-1}\) at \(STP,\) molar volume of an ideal gas is \(\left.22.7\, L\, mol^{-1}\right]\)

A \(127\)
B \(1270\)
C \(17\)
D \(452\)

Verified Solution

Answer & Solution

Correct Answer

(A) \(127\)

Step-by-step Solution

Detailed explanation

At anode \(2 H _{2} O \rightarrow O _{2}( g )+4 H ^{+}+4 e ^{-}\) At cathode \(2 H ^{+}+2 e ^{-} \rightarrow H _{2}( g )\) Now number of gm eq. \(=\frac{i \times t }{96500}\) \(=\frac{0.1 \times 2 \times 60 \times 60}{96500}\) \(=0.00746\)…

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

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