Question

When coal burns in the air ........... gas is mainly produced

• A. ${\mathrm{SO}}_2$
• B. ${\mathrm{NO}}_2$
• C. $\mathrm{CO}$
• D. ${\mathrm{CO}}_2$

Answer 1

The correct option is D

${\mathrm{CO}}_2$

Explanation for the correct option

(D) ${\mathrm{CO}}_2$

• Coal is nothing but a carbon source.
• When coal is heated in presence of air (i.e. oxygen), carbon dioxide gas will be formed.

$\mathrm{C}\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to {\mathrm{CO}}_2\left(\mathrm{g}\right)$

So, this is the correct option.

Explanation for the incorrect options

Since, ${\mathrm{SO}}_2$, ${\mathrm{NO}}_2$ and $\mathrm{CO}$ gas is not produced by the burning of coal in air. Therefore, options (A), (B) and (C) stand incorrect.

Hence, the correct option is (D) ${\mathrm{CO}}_2$.