Question

A Lewis acid 'X' reacts with LiAlH$_4$ in either medium to give a highly toxic gas, 'Y'. 'Y' when heated with NH$_3$ gives a compound known as inorganic benzene. 'Y' burns in oxygen and gives H$_2$O and 'Z'. 'Z' is:

• A. Basic oxide
• B. Acidic oxide
• C. Amphoteric acid
• D. Neutral oxide

Hint:

When a compound burns in oxygen and forms an acidic product, it is likely to be an acidic oxide. Remember, acidic oxides form acidic solutions when dissolved in water.

Answer 1

The Correct Option is B

Given that 'X' reacts with LiAlH$_4$ to give a toxic gas 'Y', and 'Y' when heated with NH$_3$ gives inorganic benzene, we can identify 'Y' as borane (BH$_3$) or its derivatives, which are known to form inorganic benzene.
- Borane (BH$_3$) is a highly reactive compound and burns in oxygen to form water (H$_2$O).
- Upon combustion, borane (BH$_3$) forms boron oxides, which are acidic in nature.
Therefore, 'Z' is an acidic oxide, as it reacts with water to form an acidic solution.
Thus, the correct answer is acidic oxide.