3.1.4.1 Enthalpy Change

Question 1

What is an exothermic reaction?

Answer 1

A reaction that gives out energy to the surrounding so the temperature increases

Question 2

What is an endothermic reaction?

Answer 2

A reaction that takes in energy from the surrounding so the temperature decreases

Question 3

What is enthalphy change?

Answer 3

The heat enerfgy transfer in a reaction at constant pressure (KJ/mol)

Question 4

What is the overall enthalpy change for an exothermic reaction?

Answer 4

Negative

Question 5

What is the overall enthalpy change for an endothermic reaction?

Answer 5

Positive

Question 6

What is the symbol for enthalpy change?

Answer 6

ΔH

Question 7

What is standard conditions?

Answer 7

100kpa or 1atm
298K or 25°C

Question 8

What are the three types of enthalpy chage?

Answer 8

Enthalpy of combustion
Enthalpy of formation
Enthalpy of reaction

Question 9

What is the definition for Enthalpy change of formation?

Answer 9

The enthalpy change when 1 mole of a substance is formed from its consistuent elements under standard states and reactants being in their standard states

Question 10

What is the symbol for Enthalpy change of formation?

Answer 10

ΔfH°

Question 11

What is the definition for Enthalpy change of combustion?

Answer 11

The enthalpy change when one mole of substance is completely byurnt in oxygen under standard conditions and reactants being in their standard states

Question 12

What is the symbol for Enthalpy change of combustion?

Answer 12

ΔcH°