Question

18. A burning splinter gets extinguished in an atmosphere of CO₂. Identify the substance which continues to burn in an atmosphere of CO₂.

• A. Coke
• B. Magnesium
• C. Sulphur
• D. Phosphorous

Answer 1

The correct option is B

Magnesium

Explanation for correct option:

(B) When magnesium burns in carbon dioxide, it forms magnesium oxide and carbon as a product. The reaction proceeds as follows:

$$\begin{gathered} 2\mathrm{Mg}\left(\mathrm{s}\right)+{\mathrm{CO}}_2\left(\mathrm{g}\right)\to 2\mathrm{MgO}\left(\mathrm{s}\right)+\mathrm{C}\left(\mathrm{s}\right) \\ \left(\mathrm{Magnesium}\right)(\mathrm{Carbon}\mathrm{dioxide})(\mathrm{Magnesium}\mathrm{oxide})\left(\mathrm{Carbon}\right) \end{gathered}$$

Explanation for incorrect options:

Coke, Sulphur, and Phosphorus do not burn in the atmosphere of CO_2, thus, the options (A), (C), and (D) are not correct.

So, the correct option is (B).