Question

multiple-choice question

which of the following is a combustion reaction?

\\(\text{c}_6\text{h}_6 + 9\text{o}_2 \
ightarrow 6\text{co}_2 + 6\text{h}_2\text{o}\\)
\\(\text{secl}_2 + \text{o}_2 \
ightarrow \text{seo}_2 + \text{cl}_2\\)
\\(\text{mgcl}_2 + \text{li}_2\text{co}_3 \
ightarrow \text{mgco}_3 + 2\text{licl}\\)

Explanation:

Identify the definition of a combustion reaction

A combustion reaction involves a hydrocarbon or organic compound containing carbon, hydrogen, and sometimes oxygen reacting with oxygen gas \(\text{O}_2\) to produce carbon dioxide \(\text{CO}_2\) and water \(\text{H}_2\text{O}\).

Analyze the given options

• Option 1: \(\text{C}_6\text{H}_6 + 9\text{O}_2

ightarrow 6\text{CO}_2 + 6\text{H}_2\text{O}\). This shows benzene (a hydrocarbon) reacting with oxygen to produce carbon dioxide and water.

• Option 2: \(\text{SeCl}_2 + \text{O}_2

ightarrow \text{SeO}_2 + \text{Cl}_2\). This is an oxidation reaction but not a standard hydrocarbon combustion producing \(\text{CO}_2\) and \(\text{H}_2\text{O}\).

• Option 3: \(\text{MgCl}_2 + \text{Li}_2\text{CO}_3

ightarrow \text{MgCO}_3 + 2\text{LiCl}\). This is a double replacement reaction.

Select the correct option

The first option matches the general form of a combustion reaction:

$$\text{C}_x\text{H}_y(\text{O}_z) + \text{O}_2 ightarrow \text{CO}_2 + \text{H}_2\text{O}$$

Answer:

• **(A) \(\text{C}_6\text{H}_6 + 9\text{O}_2

ightarrow 6\text{CO}_2 + 6\text{H}_2\text{O}\) (Correct answer)**

• (B) \(\text{SeCl}_2 + \text{O}_2

ightarrow \text{SeO}_2 + \text{Cl}_2\)

• (C) \(\text{MgCl}_2 + \text{Li}_2\text{CO}_3

ightarrow \text{MgCO}_3 + 2\text{LiCl}\)