Question

Nitrogen gas is obtained by thermal decomposition of

• A. Ba(NO₃)₂
• B. Ba(N₃)₂
• C. NaNO₂
• D. NaNO₃

Answer 1

The Correct Option is B

To determine which compound releases nitrogen gas upon thermal decomposition, let's examine each option and their decomposition reactions:

1. Barium Nitrate, Ba(NO₃)₂:

   Upon heating, barium nitrate decomposes as follows:

   Ba(NO_{3})_{2} \to BaO + 2NO_{2} + \frac{1}{2}O_{2}

   This reaction produces nitrogen dioxide (NO_{2}) and oxygen (O_{2}), but not nitrogen gas (N_{2}).

2. Barium Azide, Ba(N₃)₂:

   Thermal decomposition of barium azide occurs as:

   Ba(N_{3})_{2} \to Ba + 3N_{2}

   This reaction releases nitrogen gas (N_{2}). Hence, this compound meets the criterion.

3. Sodium Nitrite, NaNO₂:

   On heating, sodium nitrite decomposes as follows:

   2NaNO_{2} \to Na_{2}O + NO_{2} + NO

   This reaction produces nitrogen dioxide (NO_{2}) and nitric oxide (NO), but not nitrogen gas.

4. Sodium Nitrate, NaNO₃:

   Thermal decomposition of sodium nitrate is given by:

   2NaNO_{3} \to 2NaNO_{2} + O_{2}

   This reaction yields sodium nitrite (NaNO_{2}) and oxygen gas, not nitrogen gas.

Based on the above decomposition reactions, the correct answer is Barium Azide, Ba(N₃)₂, as it is the only compound among the options that decomposes to release nitrogen gas (N_{2}).