Flashcards in 18.104.22.168 Ionisation Energy Deck (12)
When does Ionisation energy occur
When atoms lose or gain electrons
What is ionisation energy
the energy needed to form positive ions
Definition of the first ionisation energy
the first ionisation energy of an element is the energy required to remove one electron from each atom in one mole of the gaseous element to form one mole of gaseous 1+ions
Describe Atomic radius
The larger the atomic radius, the smaller is the nuclear attraction experienced by the outer electrons. This is because the positive charge of the nucleus is further away from the outermost electron.
Describe Nuclear charge
The higher the nuclear charge, more protons, the larger is the attractive force on the there outer electrons
What is the electrons shielding
its when the inner shells of electrons repel
Describe electron shielding
the more inner shells there are, the larger is the shielding effect and the smaller is the nuclear attraction experienced by the outer electrons
Why is each succesive ionisation energy higher than the one before?
> As each electrons is removed, there is less repulsion between the remaining electrons and each shell will be drawn in slightly closer to the nucleus
>The positive nuclear charge will outweigh the negative charge every time an electron is removed
> As the distance of each electron from the nucleus decreases slightly, the nuclear charge attraction increases therefore more energy is needed to remove each successive electron.
Describe ionisation energy across a period
The first ionisation energy increases:
> Nuclear charge increases across a period,
> Electron shielding remains the same
> Atomic radius decreases which results in an increase in clear attraction on the outer electron
Describe Ionisation energy down a group
The first ionisation energy decreases:
> Electron shielding increases
> Atomic radius increases which causes a
> Decrease on nuclear attraction
Describe ionisation energy between group 2 and 13 element (Be --> B)
decreases This is because group 13 outermost electron is in a p orbital and group 2 element have theirs in s orbital and p have higher energy than s as they are further away from the nuclei so electrons are easier to be removes.