First ionisation energy

Question 1

First ionisation

Answer 1

The minimum amount of energy required to remove the most loosely bound electron from its neutral gaseous atom in its ground state

Question 2

Does the first ionisation energy increase or decrease going down and why?

Answer 2

Decreases going down
-increase in atomic radius
-increase in screening effect

Question 3

Does the first ionisation energy increase or decrease going across and why?

Answer 3

Increase going across
-decreasing atomic radius
-increase in effective nuclear charge

Question 4

Second ionisation energy

Answer 4

The energy required to remove an electron from an ion with a positive charge in its gaseous state