Group 2 Flashcards
What do the ions of group 2 react to form?
Ions with a 2+ charge.
What is the trend in atomic radius?
Increases down the group
What is the trend in ionisation energies?
Decreases, atomic radius increases so more shielding and less attraction from the nucleus to the delocalised electrons.
What is the trend in the strength of the metallic bonding?
Decreases going down the group as atomic radius increases attraction between electrons and positive ions decreases.
What is the trend in reactivity?
Increases going down the group as it gets easier to lose their outer electrons.
Do group 2 metals act as oxidising or reducing agents?
Reducing agents as they donate electrons.
How does magnesium react with water?
Mg + 2H2O –> Mg(OH)2 + H2
How does magnesium react with steam?
Mg + H2O –> MgO + H2
How do calcium, strontium and barium react with water?
Ca + 2H2O –> Ca(OH)2 + H2
What is the trend in solubility of group 2 sulfates?
Decreases down the group
What is the trend in solubility of group 2 hydroxides?
Increases down the group.
What is a use for magnesium hydroxide?
Neutralises stomach acid.
What is a use for calcium hydroxide?
Lime water.
What is a use for barium sulfate?
Used to line the gut to take an x-ray.
How would you test for sulfate ions in solution?
Acidify the solution with nitric or hydrochloric acid, then barium chloride is added to the solution. If a sulfate is present then a white precipitate of barium sulfate is formed.
What is the equation for the extraction of titanium?
TiCl4 + 2Mg –> 2MgCl2 + Ti
Outline the practical steps to determine the soubility of Ca(OH)2.
Take a known volume of the saturated solution. Evaporate the filtrate to dryness. Weigh the residue.
What is the equation for the thermal decomposition of ZnCO3 to ZnO?
ZnCO3 –> ZnO + CO2
How could you remove soluble impurities from a sample of Mg(OH)2?
Wash with water.
Give one advantage of using Mg(OH)2 rather than MgCO3 to reduce acidity int he stomach.
Does not produce CO2.
