Question

the reaction of carbon dioxide with hydrogen to form carbon monoxide and water proceeds as follows: co₂(g) + h₂(g) → co(g) + h₂o(g). when 15.8 grams of co₂(g) react with sufficient h₂(g), 14.8 kj of energy are absorbed. what is the value of δh for the chemical equation given? δh = kj

Explanation:

Step1: Calculate moles of CO₂

The molar mass of CO₂ is $M = 12.01+2\times16.00=44.01\ g/mol$. The number of moles of CO₂, $n=\frac{m}{M}$, where $m = 15.8\ g$. So $n=\frac{15.8\ g}{44.01\ g/mol}\approx0.359\ mol$.

Step2: Determine $\Delta H$

We know that when 0.359 mol of CO₂ reacts, 14.8 kJ of energy is absorbed. For 1 - mole of CO₂ in the reaction $CO_2(g)+H_2(g)
ightarrow CO(g)+H_2O(g)$, we can set up a proportion. Let $\Delta H$ be the enthalpy - change for the reaction. Then $\frac{\Delta H}{1\ mol}=\frac{14.8\ kJ}{0.359\ mol}$. Solving for $\Delta H$, we get $\Delta H=\frac{14.8\ kJ}{0.359\ mol}\times1\ mol\approx41.2\ kJ$.

Answer:

41.2