ES - Electron Structure

Question 1

Dot and cross diagram to show the binding in NH4+

Answer 1

Question 2

Shape and angle for 4 bonded pairs

Answer 2

Tetrahedral
109.5

Question 3

She noticed that when the ammonium chloride was solid it did not conduct electricity. However, when it was dissolved in water, the resulting solution did conduct electricity.
Explain these observations

Answer 3

Ions cannot move in a solid
Ions are free to move in a solution

Question 4

Define the term first ionisation energy

Answer 4

The energy required to remove one electron
From one mole of atom
Of gaseous atoms

Question 5

Suggest why the second ionisation of oxygen has a greater value than the first ionisation energy of oxygen

Answer 5

Shielding is smaller

Question 6

State what is meant by there term atomic number

Answer 6

Number of protons

Question 7

Formula for number of electrons that completely fill a shell

Answer 7

2 x n squared

Question 8

Explain how the information in the table above provides evidence for two electron shells in oxygen

Answer 8

Large difference between 6th and 7th IEs
Marking a different shell

Question 9

Explain why the ionisation energies show a general increase accross period 2

Answer 9

• Increasing nuclear charge
• Same shielding

Question 10

Explain why the first ionisation energy of B is less than that of Be

Answer 10

In B, electron being removed is at a higher energy
An S electron is being lost in Be
A P electron is lost in B

Question 11

Why is bromine classified as a P block element?

Answer 11

Highest energy subshell