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 ______ $\mathrm{cm}^{3}$. (Nearest integer) [Given: Faraday constant F $=96500\,\mathrm{C\,mol}^{-1}$ at STP, molar volume of an ideal gas is $22.7\,\mathrm{L\,mol}^{-1}$]

JEE Main · 2022 · 29 Jun 2022 · Shift 1 · Redox Reactions and 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)
[Given: Faraday constant F

= 96500 C mol^{- 1}

at STP, molar volume of an ideal gas is

22.7 L mol^{- 1}

]

Answer: 127

Solution

At anode:

2 H_{2} O \to O_{2} + 4 H^{+} + 4 e^{-}

At cathode:

2 H^{+} + 2 e^{-} \to H_{2}

Charge passed

Q = i \times t = 0.1 \times 2 \times 3600 = 720 C

Equivalents

= \frac{720}{96500} = 0.00746

For

O_{2}

(4 electrons per mole): moles

= \frac{0.00746}{4} = 0.001865

, volume

= 0.001865 \times 22.7 = 0.0423 L

For

H_{2}

(2 electrons per mole): moles

= \frac{0.00746}{2} = 0.00373

, volume

= 0.00373 \times 22.7 = 0.0846 L

Total volume

= 0.0423 + 0.0846 = 0.1269 L = 126.9 mL \approx 127 cm^{3}

JEE Main · 2022 · 29 Jun 2022 · Shift 1 · Integer answer

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JEE Main · 2022 · 29 Jun 2022 · Shift 1 · Redox Reactions and Electrochemistry

Solution

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