Energy Profiles

Question 1

Definition of enthalpy

Answer 1

Total amount of energy or heat content within a substance

Question 2

Definition of heat of reaction

Answer 2

Change in enthalpy during a chemical reaction

Question 3

Formula of enthalpy change/heat of reaction

Answer 3

Enthalpy change = product energy - reactant energy

Question 4

Definition of endothermic reactions

Answer 4

A reaction in which more energy is absorbed than released

Question 5

Definition of exothermic reactions

Answer 5

A reaction in which more energy is released than absorbed

Question 6

Enthalpy change of endothermic reaction

Answer 6

Positive

Question 7

Enthalpy change of exothermic reaction

Answer 7

Negative

Question 8

Definition of activation energy

Answer 8

Minimum amount of energy needed to start a chemical reaction

Question 9

Definition of activated complex

Answer 9

Molecules are broken down into free atoms before they bond to form products

Question 10

What is needed for a reaction to occur?

Answer 10

Reactant molecules should collide

Question 11

What do molecules need to collide and break bonds?

Answer 11

Energy