ionisation energies

Question 1

what is the definition of first ionisation energy

Answer 1

The energy required to remove 1 e- from each atom in 1 moles of gaseous atoms of an element to form 1 mole of gaseous 1+ ions

Question 2

which factors effect ionisation energy

Answer 2

Nuclear charge
Atomic Radius
e- sheilding

Question 3

what is second ionisation energy

Answer 3

the energy required to remove 1 e- from each ion in 1 mole of gaseous 1+ ions of an element to for 1 mole of 2+ ions

Question 4

How do successive ionisation energies prove the existence of shells

Answer 4

as you keep ionising an element, the successive ionisation energies steadily increase. But when moving shells the ionisation energy suddenly jumps up doe to decreased atomic radius electron shielding

Question 5

how do successive FIRST ionisation energies prove the existence of sub shells

Answer 5

from beryllium to boron you would expect first ionisation energy to rise but instead it falls. This is because Be has a full P sub shell which is at a lower energy level and more stable than a P sub shell with only 1 e-

Question 6

Explain the difference in ionisation energy between nitrogen and oxygen

Answer 6

nitrogen has a half full p sub shell. This is more stable than oxygens P sub shell which has 1 orbital with paired e- and 2 with unpaired e-. This is because the e- in this orbitals repel each other