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1

Define the term standard lattice enthalpy

The enthalpy change when one mole of ionic lattice is formed from its gaseous ions under standard conditions

2

Give an example reaction equation that shows standard lattice enthalpy

Sodium ion(g) + Chloride ion(g) → NaCl(s)

Calcium ion(g) + Oxygen ion (g) → CaO(s)

3

Define the term standard enthalpy change of formation

The enthalpy change when one mole of compound is formed from its elements in their defined standard states under standard conditions

4

Give an example reaction equation that shows standard enthalpy change of formation

K(s) + 1/2F2(g) → KF(s)
2C(s) + 3H2(g) + 1/2O2 (g) → C2H5OH

5

Define the term standard enthalpy change of atomisation

The enthalpy change when one mole of gaseous atoms is from from its elements in their defined standard states under standard conditions

6

Give an example reaction equation that shows standard enthalpy change of atomisation

K(s) → K(g)
1/2Br2 (s) → Br2(g)

7

Define the term first ionisation energy

The amount of energy required to remove one mole of electrons from one mole of gaseous atoms.

8

Give an example reaction equation that shows first ionisation energy

Na → Na^+ + e^-
O → O^+ + e^-

9

Define the term second ionisation energy

The amount of energy that accompanies the formation of one mole of gaseous 2+ ions from 1 mole of gaseous 1+ iions

10

Give an example reaction equation that shows second ionisation energy

Na^+ → Na^2+ + e^-
O^+ → O^2+ + e^-

11

Define the term first electron affinity

The enthalpy change that accompanies the formation of one mole of gaseous 1^- ions from gaseous atoms

12

Give an example reaction equation that shows first electron affinity

Cl(g) + e^- → Cl^-(g)
1/2F2(g) + e^- → F^-(g)

13

Define the term second electron affinity

The enthalpy change that accompanies the formation of one mole of gaseous 2^- ions from one mole of gaseous 1^- ions.

14

Give an example reaction equation that shows first electron affinity

Cl^-(g+ e^- → Cl^2-(g)
F^-(g) + e^- → F^-(g)

15

What are the standard conditions

100kPa and 298Kelvin

16

Is Lattice Enthalpy always endothermic or always exothermic?

Always EXOTHERMIC

17

What factors determine lattice enthalpy?

Ionic size and Ionic charge

18

How does a decreasing ionic size affect lattice enthalpy?

Smaller ions have a higher charge density. This means that the ions attract to each other more strongly. Therefore, more energy is released when bonds form. Therefore, the smaller the ionic radius, the bigger the lattice enthalpy

19

How does an increasing ionic size affect lattice enthalpy?

Bigger ions have a smaller charge density. This means that the ions attract to each other more weakly. Therefore, less energy is released when bonds form. Therefore, the bigger the ionic radius, the smaller the lattice enthalpy

20

How does an increasing ionic chargevaffect lattice enthalpy?

The higher the charge on the ions, the more energy is released when an ionic lattice forms. This is due to the stronger electrostatic forces between the ions. Therefore, the higher the ionic charge, the larger the lattice enthalpy

21

How does a decreasing ionic charge affect lattice enthalpy?

The smaller the charge on the ions, the less energy is released when an ionic lattice forms. This is due to the weaker electrostatic forces between the ions. Therefore, the smaller the ionic charge, the smaller the lattice enthalpy

22

Higher lattice enthalpy means a higher or lower negative value?

Higher

23

What factors affect ionisation energy?

Nuclear charge
Shielding
Atomic radius

24

Greater nuclear charge = _______ ionisation energy. Why?

Higher. This is because the outermost electrons are more strongly attached to the nucleus. Therefore, more energy is needed to remove one mole of electrons from a gaseous atom.

25

Greater shielding = _______ ionisation energy. Why?

Lower. This is because the outermost electrons are less strongly attached to the nucleus. Therefore, less energy is needed to remove one mole of electrons from a gaseous atom.

26

Greater atomic radius = _______ ionisation energy. Why?

Lower. This is because the outermost electrons are further away from the nucleus. Therefore, they are less strongly attached to the nucleus. This means that less energy is needed to remove one mole of electrons from a gaseous atom.

27

What is a Born-Haber Cycle and what is it used to do?

A Born-Haber cycle is an indirect cycle which allows us to find lattice enthalpy for a reaction.

28

What does a generic Born-Haber cycle look like?

TOP

First IE
↑ Electron affinity
Atomisation ↓
↑ ↓
Atomisation ↓
↓ ↓
Formation - Formation - Formation - Formation

BOTTOM

29

What thing must you include in a Born-Haber cycle?

State symbols
Direction of arrows
Diatomic?
Name of steps (e.g. enthalpy change of atomisation)
What do you times by 2 or 3 etc
- Exothermic or endothermic (Watch out for 2nd electron affinity)
- Balancing charges

30

In the Born-Haber cycle for a group 1 and group 7 element, do we times anything by 2 or 3?

NO