Enthalpy Changes

Question 1

what are the standard conditions

Answer 1

25 degrees / 298K
100kpa pressure
Normal physical state

Question 2

definition of enthalpy change of reaction

Answer 2

Amounts of reactants shown in the equation react to give products under standard conditions

Question 3

definition of enthalpy change of formation

Answer 3

One mole of compound is formed from its elements under standard conditions

Question 4

definition of enthalpy change of combustion

Answer 4

One mole of substance is burnt in excess oxygen under standard conditions

Question 5

definition of enthalpy change of neutralisation

Answer 5

One mole of water is formed by reaction of acid and alkali under standard conditions

Question 6

definition of enthalpy change of solution

Answer 6

One mole of solute is dissolved in a solvent to form an infinitely dilute solution under standard conditions

Question 7

definition of enthalpy change of atomisation

Answer 7

one mole of gaseous atoms is formed from its elements under standard conditions

Question 8

definition of enthalpy change of hydration of anhydrous salt

Answer 8

One mole of a hydrated salt formed from one or more of anhydrous salt under standard conditions

Question 9

what does exothermic energy graph look like

Answer 9

more energy released when products formed

Question 10

what does endothermic energy graph look like

Answer 10

more energy released when bonds are broken