Question

How many moles of methane are required to produce $11\ \text{g}$ $CO_{2(g)}$ after combustion? (Molar mass of $CO_{2}=44\ \text{g mol}^{-1}$)

• A. 0.25
• B. 0.5
• C. 1.5
• D. 2.0
• E. 2.5

Hint:

In a 1:1 molar ratio reaction, the moles of product required equal the moles of reactant used.

Answer 1

The Correct Option is A

Step 1: Concept
The combustion of methane ($CH_{4}$) follows the reaction: $CH_{4} + 2O_{2} \rightarrow CO_{2} + 2H_{2}O$. One mole of $CH_{4}$ produces one mole of $CO_{2}$.

Step 2: Meaning
Calculate the number of moles of $CO_{2}$ using the formula $n = \frac{m}{M}$.

Step 3: Analysis
$n(CO_{2}) = \frac{11~g}{44~g~mol^{-1}} = 0.25~mol$. Since the ratio is 1:1, $n(CH_{4}) = 0.25~mol$.

Step 4: Conclusion
Hence, 0.25 moles of methane are required. Final Answer: (A)