Concept:To determine reacting amounts, we must first write and balance the complete combustion equation for the specified alkane.
Formula:$$ \text{C}_3\text{H}_8 + 5\text{O}_2 \rightarrow 3\text{CO}_2 + 4\text{H}_2\text{O} $$
Solution:- Propane is an alkane with the chemical formula \( \text{C}_3\text{H}_8 \).
- The balanced combustion equation shows that 1 single mole of propane strictly requires 5 moles of oxygen gas to combust completely. (The ratio is 1:5).
- The question asks for the oxygen needed to combust 2 moles of propane.
- Since the propane amount is doubled, the oxygen amount must also double: \( 5 \times 2 = 10 \text{ moles} \).
Why other options are incorrect:- 8, 12, 14: These values result from incorrectly balancing the chemical equation, likely making errors in tracking the oxygen atoms distributed between the \( \text{CO}_2 \) and \( \text{H}_2\text{O} \) products.
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