Module 3

Question 1

Where has evidence for how the electrons are arranged in atoms come from

Answer 1

Ionisation energies

Question 2

What is the 1st ionisation energy

Answer 2

Energy required to remove one electron from each atom in a mole of gaseous atoms producing one mole of 1+ ions

Question 3

What is the 2nd ionisation energy

Answer 3

Energy required to remove only the second electrons

Question 4

1st and 2nd ionisation energy of Na

Answer 4

1st] Na(g) —> Na+(g) + e-
2nd] Na+(g) —> Na2+(g) + e-

Question 5

What three factors affect ionisation energy

Answer 5

Distance from the nucleus
Electron shielding
Nuclear charge

Question 6

Balance for ionisation energy

Answer 6

Nuclear charge. Distance, shielding
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Question 7

Ionisation energy as you go down a group

Answer 7

As you go down the group, the ionisation energy decreases and the element have more shells, as distance of outer electron from nucleus increases so does shielding

Question 8

Explanation for generals increase in ionisation energy as you go across a period

Answer 8

The nuclear charge increases, shielding stays the same, distance decreases slightly

Question 9

Exception of general increase of ionisation energy between group 2-3 explanation

Answer 9

2p subshell higher energy than 2s so 2p electron easier to remove

Question 10

Exception of general increase of ionisation energy between group 2-3 explanation

Answer 10

llhighest energy in 2p, but paired in 6- electrons repel making it easier for them to be removed

Question 11

When are successive ionisation energies greater

Answer 11

After 1st electron, remaining electrons pulled closer yo nucleus, nuclear attraction increases so more energy needed

Question 12

How do successive ionisation energies allow predictions about number of electrons in the outer shell .’. Group .’. Element

Answer 12

If there’s a large increase is successive ionisation energies electron has been removed from shell closer to the nucleus with less shielding