Question

The reaction of carbon dioxide(g) with hydrogen(g) to form acetylene(g) (C2H2) and water(g) proceeds as follows: 2 CO2(g) + 5 H2(g) C2H2(g) + 4 H2O(g) When 11.1 grams of CO2(g) react with sufficient H2(g) , 5.86 kJ of energy are absorbed . What is the value of H for the chemical equation given? ΔHrxn = kJ

Answer 1

Answer: 46.5 kJ

Explanation:

The balanced chemical reaction is:

$2CO_2(g)+5H_2(g)\rightarrow C_2H_2(g)+4H_2O$

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

given mass = 11.1 g

Molar mass = 44.01 g/mol

$\text{Number of moles of carbon dioxide}=\frac{11.1g}{44.01g/mol}=0.252moles$

0.252 moles of carbon dioxide react with sufficient hydrogen, energy released = 5.86 kJ

2 moles of carbon dioxide react with sufficient hydrogen, energy released =$\frac{5.86 kJ}{0.252}\times 2=46.5kJ$

Thus value of ΔHrxn for the chemical equation given is 46.5 kJ