Question

A potential energy diagram is shown

What is the total change in enthalpy of this reaction?

Answer 1

B. 25 kj

Step-by-step explanation:

Products-reactants

I took the exam

Answer 2

Given↷

• PE of products⇢ 55kJ
• PE of reactants⇢30kJ
• Activation energy⇢65kJ

To find↷

• Total change in enthalpy of the reaction

Answer↷

• 25kJ

Solution↷

we know that,

AᵣH = (Sum of enthalpies of products)-(Sum of enthalpies of reactants)

AᵣH = 55kJ - 30 kJ

AᵣH = 25kJ

or

AᵣH =( Activation Energy-Reactant energy) +( Activation Energy-product energy)

AᵣH =(65kJ -30kJ) +(65kJ-55kJ)

• Since there's a degrade , we'll consider the PE of product as -ve

AᵣH = 35kJ - 10kJ

AᵣH = 25kJ