Trends of Period 3 Elements: First Ionisation Energy Flashcards
1
Q
The first ionisation energy (IE1) is the
A
energy required to remove one mole of electrons from one mole of atoms of an element in the gaseous state to form one mole of gaseous ions
Eg. the first ionisation energy of Na is:
Na (g) → Na+ (g) + e-
2
Q
There is a general increase in IE1 across a period as
A
The nuclear charge increases
The atomic radius decreases
There are stronger attractive forces between the nucleus and outer electrons
It therefore gets harder to remove any electrons
Small ‘dips’ are observed between Mg - Al and P - S