Lattice enthalpy

Question 1

Define Lattice enthalpy

Answer 1

The enthalpy change for the formation of 1 mole of ionic lattice from gaseous ions

Question 2

What is a Born-Haber cycle

Answer 2

A diagram which represents lattice enthalpy

Question 3

Define first ionisation energy

Answer 3

The enthalpy change required to turn one mole of gaseous atoms into one mole of gaseous 1+ ions by removing one mole of electrons

Question 4

Define standard enthalpy of formation

Answer 4

The enthalpy change required to form one mole of a compound from its constituent elements in their standard states

Question 5

What does it mean if there is a high lattice enthalpy

Answer 5

The ionic lattice is strong, the higher the lattice enthalpy, the stronger the ionic lattice

Question 6

Is lattice enthalpy always endothermic or exothermic

Answer 6

Exothermic

Question 7

What is electron affinity?

Answer 7

Turning non-metal gaseous atoms into negative non-metal ions

Question 8

Is first election affinity always exothermic or endothermic?

Answer 8

Endothermic

Question 9

Is second electron affinity exothermic or endothermic?

Answer 9

Exothermic

Question 10

Deduct a half equation to show first ionisation of sodium

Answer 10

Na(g) —> Na+(g) + e-

Question 11

Deduce the half equation to show the first electron affinity of oxygen

Answer 11

O(g) + e- —> O-(g)

Question 12

Starting from the start of the cycle, name the process of the born-haber cycle, ending at lattice enthalpy

Answer 12

Enthalpy of formation
Atomisation of metal
Atomisation of non-metal
1st ionisation energy 
(2nd ionisation energy)
1st electron affinity
(2nd electron affinity) 
Lattice enthalpy

Question 13

When travelling down an arrow which is pointing in the opposite direction, what is the rule?

Answer 13

Make the value the opposite sign (-/+)