Question

Assertion :If $30$ mL of $H_2$ and $20$ mL of $O_2$ react to form water, then $5$ mL of $H_2$ is left at the end of the reaction. Reason: $H_2$ is the limiting reagent.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Assertion is incorrect but Reason is correct.

Answer 1

The correct option is D Assertion is incorrect but Reason is correct.

$\underset{30mL}{H_2}+\underset{15mLreacted}{\frac{1}{2}{O}_2}\to H_{2}O$

Volume of $O_2$ left $=20-15=5mL$

(R) is correct, since $H_2$ is completely consumed, and hence is the limiting reagent.