Question

gaseous acetylene (c₂h₂) reacts with oxygen gas to form gaseous carbon dioxide and gaseous water. express your answer as a chemical equation including phases. c₂h₂(g) + 5o(g)→2co₂(g) + h₂o(g) a chemical reaction does not occur for this question.

Explanation:

Step1: Write unbalanced equation

$\text{C}_2\text{H}_2(g) + \text{O}_2(g)
ightarrow \text{CO}_2(g) + \text{H}_2\text{O}(g)$

Step2: Balance C atoms

$\text{C}_2\text{H}_2(g) + \text{O}_2(g)
ightarrow 2\text{CO}_2(g) + \text{H}_2\text{O}(g)$

Step3: Balance H atoms

(Already balanced: 2 H on both sides)

Step4: Balance O atoms

Right side: $2\times2 +1=5$ O → Left side needs $\frac{5}{2}\text{O}_2$; multiply all by 2 to eliminate fraction: $2\text{C}_2\text{H}_2(g) +5\text{O}_2(g)
ightarrow4\text{CO}_2(g)+2\text{H}_2\text{O}(g)$

Answer:

$2\text{C}_2\text{H}_2(g) + 5\text{O}_2(g)
ightarrow 4\text{CO}_2(g) + 2\text{H}_2\text{O}(g)$