Question

Calculate ΔHᵣₓₙ​ for the reaction:

CH₄​(g)+4Cl₂​(g)⟶CCl₄​(g)+4HCl(g)

using the following information:

C(s)+2H₂(g)⟶CH₄(g)ΔH=−74.6kJ C(s)+2Cl₂​(g)⟶CCl₄​(g)ΔH=−95.7kJ H₂​(g)+Cl₂​(g)⟶2HCl(g)ΔH=−92.3kJ

a. -444.2 kJ
b. -418.4 kJ
c. -401.0 kJ
d. -365.4 kJ

Answer 1

To calculate the enthalpy change for the given reaction, we need to sum up the enthalpy changes of each individual reaction involved. The correct answer is -365.4 kJ.

Step-by-step explanation:

The enthalpy change (ΔHᵣᵐ) for the reaction:

CH₄(g) + 4Cl₂(g) ⟶ CCl₄(g) + 4HCl(g)

can be calculated by summing the enthalpy changes of each individual reaction involved.

First, we need to calculate the enthalpy change for the formation of CH₄(g) from its elements C(s) and H₂(g), which is -74.6 kJ.

Next, we calculate the enthalpy change for the formation of CCl₄(g) from its elements again, which is -95.7 kJ.

Finally, we calculate the enthalpy change for the formation of 4HCl(g) from H₂(g) and Cl₂(g), which is -92.3 kJ.

We can then sum up these enthalpy changes:

ΔHᵣᵐ = -74.6 kJ + (-95.7 kJ) + (-92.3 kJ) = -262.6 kJ

Therefore, the correct answer is d. -365.4 kJ.