Question

using enthalpy diagrams
consider these equations.
ch₄(g) → c(s) + 2h₂(g) δh₁ = 74.6kj
c(s) + 2cl₂(g) → ccl₄(g) δh₂ = -95.7kj
2h₂(g) + 2cl₂(g) → 4hcl(g) δh₃ = -184.6kj
ch₄(g) + 4cl₂(g) → ccl₄(g) + 4hcl(g) δh₄ = -205.7kj
complete this based on the diagram.
arrow d:
represents an intermediate reaction
has a magnitude that is always higher than any intermediate reaction
represents the overall enthalpy of reaction

Explanation:

Step1: Recall Hess's Law concept

Hess's Law states that the enthalpy change of an overall reaction is the sum of the enthalpy changes of the individual - step reactions. The overall reaction enthalpy is represented by the net change from the initial state to the final state on an enthalpy diagram.

Step2: Analyze the role of arrows in enthalpy diagram

In an enthalpy diagram, the overall reaction is represented by the arrow that goes from the reactant - energy level to the product - energy level. Intermediate reactions are steps within the overall reaction mechanism. The arrow representing the overall enthalpy of reaction shows the net energy change for the entire reaction process.

Answer:

represents the overall enthalpy of reaction