Question

Magnesium wire continues to burn in the atmosphere of $CO_2$,though $CO_2$ is not a supporter of combustion because

• A. Mg acts as an oxidising agent
• B. Mg has high ionization energy
• C. Mg acts as a reducing agent and removes oxygen from $CO_2$
• D. All of the above

Answer 1

Answer: (C)

Mg acts as a reducing agent and removes oxygen from $CO_2$

Answer 2

Mg is more electropositive than carbon and has more affinity for $O_2$ than that of C. As such the enthalpy of formation of MgO is more than that of $CO_2$, therefore, Mg continues to bum in $CO_2$ ${CO_2 + 2Mg -> 2MgO + C}$