Group 2 Flashcards
What happens to atomic radius down group 2 and why?
Increases down the group because extra electron shells added
What happens to 1st ionisation energy down group 2 and why?
Decreases down the group; each element has an extra electron shell than the one above. More inner shells shield outer electrons from nuclear attraction, meaning it’s easier to lose outer electrons.
What happens to melting point down group 2? And why?
Decreases. Group 2 Metals have metallic structures, down the group, ions get bigger( no. Of delocalised electrons and charge on ions stays the same.) The larger the ionic radius, the further away the delocalised electrons are from the nucleus, so feel less attraction.
How does group 2 reactivity change down the group?
Reactivity increases down the group
Group 2 metal and water
= metal hydroxide + hydrogen
How are group 2 metals used in extraction of titanium
Titanium ore converted to titanium chloride from titanium oxide by heating with carbon in a stream of chlorine gas
Titanium chloride then purified by fractional distillation, before being reduced by magnesium in a furnace.
Titanium chloride and magnesium reaction.
TiCI4 + 2Mg → Ti + 2MgCl2
Compounds that contain singly charged negative ions e.g. OH - (solubility)
Increase in solubility down the group
Compounds that contain doubly charged negative ions e.g. SO4 2- (solubility)
Decrease in solubility down the group
How is Mg(OH)2 used?
Used in indigestion tablets as an antacid - neutralises excess stomach acid
How is Ca(OH)2 used?
Used in agriculture to neutralise acidic soils
How is CaO and CaCO3 used
Used to remove acidic sulfur dioxide from flue gases- wet scrubbing
Slurry made by mixing CaO or CaCO3 with water. Sprayed onto flue gases to produce solid waste product calcium sulfide
Calcium oxide reaction removing acidic sulfur dioxide from flue gases
CaO + 2H2O + SO2 → CaSO3 + 2H2O
CaCO3 reaction removing acidic sulfur dioxide from flue gases.
CaCO3 + 2H2O + SO2 → CaSO3 + 2H2O + CO2
What ions can you test for using acidified barium chloride?
Sulfate ions and white precipitate formed
