Enthalpy Change

Question 1

What are the 3 standard conditions?

Answer 1

1) temperature = 298K
2) pressure = 100KPa
3) concentration 1 mol/dm3

Question 2

Exothermic Reactions:

Answer 2

gives energy to the environment triangleH -

Question 3

Endothermic Reactions:

Answer 3

absorbs energy from the environment triangleH +

Question 4

Enthalpy change:

Answer 4

heat energy measured at a constant pressure

Question 5

“of reaction”

Answer 5

amount of energy released when equation is balanced

Question 6

standard enthalpy change of reaction:

Answer 6

the enthalpy change when the reactants in the stoichiometric equation react to give the products under standard conditions

Question 7

standard enthalpy change of formation:

Answer 7

the enthalpy change when one mole of a compound is formed from its elements under standard conditions (Hess cycles)

Question 8

standard enthalpy change of combustion:

Answer 8

the enthalpy change when one mole of substance is burnt in excess oxygen under standard conditions

Question 9

standard enthalpy change of neutralisation:

Answer 9

the enthalpy change when one mole of water is formed by reacting an acid and alkali under standard conditions

Question 10

Energy transferred equation J:

Answer 10

mass (Kg) * specific heat capacity (J/Kg/degrees C) * change in temperature (degrees C)