BLOCK 4 Ionisation energy Flashcards
Molar first ionisation energy definition
energy required to remove 1 mole of electrons from 1 mole of its gaseous atom to form 1 mole of 1+ ions
X(g) –> X+(g) +e-
Molar second ionisation energy definition
energy required to remove 1 mole of electrons from a mole of 1+ ions to form 1 mole of 2+ ions
how does ionisation energy change attraction
The greater the attraction, the greater the ionisation energy
What does attraction depend on?
size of nuclear charge
The distance of the outer electron for the nucleus
The shielding effect by electrons (in filled inner shells.)
size of nuclear charge
- Greater the nuclear charge, greater the attractive force
The distance of the outer electron for the nucleus
- The further the distance, the lower the attractive
force
The shielding effect by electrons (in filled inner shells.)
- It’s the repulsion between electrons in different shells.
- Electrons are all negative so repel each other.
- The more filled inner shells, the lower the ionisation energy.
On a graph of first ionisation energy, which group occupy peaks
group 0
On a graph of first ionisation energy, which group occupy troughs
group 1