Structure 1.3

Question 1

First ionisation energy

Answer 1

The energy required to remove one electron from an atom in the gaseous state

Question 2

What is ionisation energy measured in?

Answer 2

kJ mol-1

Question 3

Periodicity

Answer 3

A repeating pattern/ recurring trend of a property

Question 4

Elements with the lowest first ionisation energies

Answer 4

Alkali metals (group one)

Question 5

Elements with the highest first ionisation energies

Answer 5

Noble Gases (group 18)

Question 6

What is evidence of the max no. of electrons in each main energy level and sub-level?

Answer 6

The patterns in a graph of the first ionisation energies for the first 86 elements repeating after 2 then 8 then 18 etc

Question 7

Why is it easier to remove an electron from a new sub-level compared to a full sub-level?

Answer 7

It is easier to remove an electron from a new sub-level because the electron is less stable and more weakly held compared to a full sub-level, where the electrons are more stable due to the filled configuration.

Question 8

Why does it require more energy to remove successive electrons from an ion?

Answer 8

Because the number of p+’s exceeds the number of remaining e-‘s, inc the attraction between the e-‘s and p+’s and dec the repulsion between e-‘s. This pulls the e- cloud closer to the nucleus and holds them tighter due to the inc electrostatic attraction. Once all valence e-‘s have been removed the energy required to remove the next e- inc sharply.

Question 9

Transitioning up energy levels is an __thermic change

Answer 9

endo(thermic)

Question 10

Transitioning down energy levels is an __thermic change

Answer 10

exo(thermic)