The number of moles of methane required to produce $11 \mathrm{~g} \mathrm{~CO}_2(\mathrm{g})$ after complete combustion is : (Given molar mass of methane in $\mathrm{g} \mathrm{~mol}^{-1}: 16$ )

<p>To find the number of moles of methane ($CH_4$) required to produce 11g of $CO_2$ upon complete combustion, we first need the balanced chemical equation for the combustion of methane:</p> <p>$CH_4 + 2O_2 \rightarrow CO_2 + 2H_2O$</p> <p>From the balanced equation, we see that 1 mole of $CH_4$ produces 1 mole of $CO_2$. Therefore, the moles of $CH_4$ needed to produce a certain amount of $CO_2$ will be equal to the moles of $CO_2$ produced.</p> <p>To find the moles of $CO_2$ produced from 11g of $CO_2$, we use the formula:</p> <p>$\text{Moles} = \frac{\text{Mass}}{\text{Molar mass}}$</p> <p>The molar mass of $CO_2$ is $44 \mathrm{~g/mol}$ (12 from carbon and 16$\times$2 from oxygen). Then, the moles of $CO_2$ produced from 11g of $CO_2$ can be calculated as:</p> <p>$$\text{Moles of } CO_2 = \frac{11 \mathrm{~g}}{44 \mathrm{g/mol}} = 0.25 \mathrm{~mol}$$</p> <p>Since the stoichiometry of the reaction between methane and oxygen is 1:1 for $CH_4$ and $CO_2$, the moles of $CH_4$ required to produce 11g of $CO_2$ is also 0.25 moles.</p> <p>Therefore, the correct answer is <strong>Option B: 0.25</strong>.</p>