# Calculate the ΔH for the reaction: C(s, graphite) + 2H2O(g) ---> CH4(g) + O2(g) using the...

## Question:

Calculate the ΔH for the reaction: {eq}\rm C(s,\;graphite) + 2H_2O(g) \to CH_4(g) + O_2(g) {/eq} using the following chemical equations and their respective enthalpy changes:

{eq}\rm C(s,\;graphite) + O_2(g) \rightarrow CO_2(g);\;\; \Delta \textit{H} = -394\;kJ.\\ CH_4(g) + 2O_2(g) \to CO_2(g) + 2H_2O(g);\;\;\Delta \textit{H} = -802\;kJ. {/eq}

## Hess's Law:

The enthalpy change for a chemical reaction can be determined with the help of Hess's law which states that the sum of the enthalpy changes in each transformation is equal to the enthalpy change for the overall reaction, no matter how many steps are involved in the reaction.

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To determine the enthalpy of the reaction, ΔH, we do this by applying Hess' law and then adding the first equation to the inverse of the second...

Using Hess's Law to Calculate the Change in Enthalpy of a Reaction

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Chapter 13 / Lesson 3
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Learn about enthalpy of reaction and enthalpy change formula. Understand what Delta H is, the Delta H equation, and how to calculate the enthalpy of reaction.