Reactivity trends in group 2

What are group 2 metals called

Alkaline earth metals

What happens to group 2 electrons in a redox reaction

They are oxidised to form 2⁺ ions

What is the trend in ionisation energy down group 2

Down group 2 ionisation energy decreases as attraction between nucleus and outer electrons decreases as a result of increasing atomic radius and increasing shielding so reactivity increases as it is easier to remove electrons

What is the trend in thermal stability down group 2

Thermal stability increases down Group 2 because ionic radius increases, so charge density decreases. The cations therefore have lower polarising power and distort the carbonate ion less, making it less likely to decompose and release carbon dioxide. As a result, higher temperatures are required to decompose the compound.

note:

Thermal stability is how resistant a compound is to heating

What is the trend in polarising power down group 2

Polarising power decreases because ionic radius increases so charge density decreases meaning carbonate ion distorted less so energy of decomposition is higher meaning there is a lower chance of carbonate breaking down to form carbon dioxide

Note:

Polarisation is the distortion of the electron cloud of negative ions by a positive ion

How does alkalinity change down group 2

Alkalinity increases as ionic radius increases so electrostatic attraction between M and OH ions decreases, so OH dissolve more easily. Solubility of M increases basically.

Uses of Group 2 metals

• Milk of magnesia, helps with indigestion as it neutralises acid causing indigestion, low solubility and gentle reaction