Group 2 Flashcards
Trend in atomic radius down group 2
Further down the larger the atomic radius, more shielding, more energy levels
Trend in ionisation energy down group 2
Further down the smaller the energy, more shielding, further away from nucleus
Trend in melting points down group 2
Decrease as you go down the group, magnesium has lowest point doe to how its atoms pack in the metallic crystal
Reaction between group 2 metals and water
All react with liquid water to produce a metal hydroxide and hydrogen. Magnesium reacts with water vapour to produce MgO and H2
Trend in reactivity
Further down group 2, metals become more reactive
Use of magnesium
Extraction of titanium from TiCl2
Why is Mg(OH)2 used in medicine
Used as indigestion remedies to neutralise excess stomach acid as it’s almost insoluble
Use of Ca(OH)2
Called slaked lime and used to treat acidic soil
Use of CaO or CaCO3
Remove SO2 from flue gases
Trend in solubility for group 2 metal hydroxides
Going down the group they become more soluble
Trend in solubility for group 2 metal sulphates
Going down the group they become less soluble
BaSO4 is
Insoluble
Use of acidified BaCl2
Used as a test for sulphate ions, forming white precipitate if a sulphate is present
Use of BaSO4
Used in medicine to be taken in by mouth to outline the gut in medical X-rays as it’s so insoluble. Barium compounds are usually toxic
Why does BaCl2 need to be acidified
Remove carbonate ions as CO2
