Question

The total enthalpy of the products in a reaction is 0 kJ, and the total enthalpy of the reactants is 100 kJ. What is the ΔH for the reaction? Choose the correct answer.

a.–393.5 kJ
b.–100 kJ
c.0 kJ
d.+100 kJ

Answer 1

Answer: b. -100 kJ

Step-by-step explanation:

Heat of reaction is the energy released or absorbed during the course of the reaction. It is represented by the symbol
`\Delta H`.

`\Delta H=H_(products)-H_(reactants)`

`\Delta H` = enthalpy of reaction = ?

`H_(products)` = enthalpy of products = 0 kJ

`H_(reactants)` = enthalpy of reactants = 100 kJ

`\Delta H=0kJ-100kJ`

`\Delta H=-100kJ`

Thus the ΔH for the reaction is -100kJ