1.1 Atomic Structure - Ionisation

Question 1

Ionisation:

Answer 1

The removal of one or more electrons

Question 2

First ionisation energy:

Answer 2

The energy needed to remove 1 electron from each atom in 1 mole of gaseous atoms to form 1 mole of gaseous 1+ ions

Question 3

What type of process is ionisation?

Answer 3

Endothermic

Question 4

Example equation with oxygen:

Answer 4

O(g) -> O+(g) + e-

Question 5

Important points:

Answer 5

Must use gas state symbol as ionisation energies are measured for gaseous atoms
Always refer to 1 mole of atoms rather than an atom
The lower the ionisation energy, the easier it is to form an ion

Question 6

3 Factors of ionisation energy:

Answer 6

Nuclear charge
Distance from nucleus
Shielding

Question 7

Nuclear charge:

Answer 7

The more protons there are in the nucleus, the stronger the force of attraction between the negative electrons and positive protons

Question 8

Distance from nucleus:

Answer 8

The closer the electron to the nucleus, the stronger the force of electrostatic attraction between them

Question 9

Shielding:

Answer 9

As the number of electrons between the nucleus and the outer shell increases, the weaker the attraction of the electrons and nucleus. This lessening of the attraction by the electrons closer to the nucleus is referred to as shielding or screening

Question 10

Second ionisation energy:

Answer 10

The energy needed to remove 1 electron from each ion in 1 mole of gaseous 1+ ions to form 1 mole of gaseous 2+ ions

Question 11

General equation for second ionisation:

Answer 11

X^(n-1) (g) -> X^n+ (g) + e-