In the reaction 2Al(s) + 6HCl(aq) → 2Al3+(aq) + 6Cl−(aq) + 3H2(g)
Q. In the reaction,

2Al(s) + 6HCl(aq) → 2Al3+(aq) + 6Cl−(aq) + 3H2(g)
A. 12 L HCl(aq) is consumed for every 6 L H₂(g) produced.
B. 11.2 L H₂(g) at STP is produced for every mole of HCl consumed.
C. 33.6 L H₂(g) is produced regardless of temperature and pressure for every mole of Al that reacts.
D. 67.2 L H₂(g) at STP is produced for every mole of Al that reacts.
Correct Answer: 11.2 L H₂(g) at STP is produced for every mole of HCl consumed.

Explanation

Balanced reaction:

2Al + 6HCl → 3H₂

From the equation:
6 moles of HCl produce 3 moles of H₂

So,
1 mole of HCl produces = 3 / 6 = 1 / 2 mole of H₂

At STP,
1 mole of any gas occupies 22.4 L

Therefore,
Hydrogen produced per mole of HCl
= (1 / 2) × 22.4
= 11.2 L

Hence, the correct statement is option B.

This type of stoichiometry question is very important for JEE Main, JEE Advanced and IIT JEE.

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