Group 2

Question 1

Physical properties of Group 2

Answer 1

Alkaline earth metal
Metal hydroxide formed
Reactive, only found in stable compounds

Question 2

Reducing agent

Answer 2

Group 2 reduces other species

Reducing agent get oxidised

Question 3

Redox reaction with oxygen

Answer 3

Forms metal oxide

2Mg(s) + O2(g) =>2MgO(s)

Question 4

Redox reaction with water

Answer 4

Form alkaline hydroxide
Reaction becomes more vigorous with metals further down group
Not all hydrogen reduced

Sr(s) + 2H2O(l) => Sr(OH)2(aq) +H2(g)

Question 5

Redox reaction with dilute acid

Answer 5

Form salt and hydrogen gas
Reaction becomes more vigorous down group

Mg(s) + 2HCl(aq) => MgCl2(aq) + H2(g)

Question 6

Trends in reactivity and ionisation energy

Answer 6

Reactivity increases down group
React by losing electrons, form 1+ ions
Ionisation energies decrease down group, increased atomic radius, increased shielding, easier to lose e-

Question 7

Reactions with water, group 2 oxides

Answer 7

Release OH-, form alkaline metal hydroxide solution
Slightly soluble in water
When solution saturated, metal and hydroxide in excess form solid precipitate of metal hydroxide

CaO(s) + H2O(l) => Ca2+(aq) + 2OH-(aq)

Question 8

Solubility of hydroxides

Answer 8

Increases down group, more alkaline solutions, pH increases

Can test this in experiment

Question 9

Use as bases

Answer 9

Used to neutralise acids
Ca(OH)2- increase pH of acidic soil, forming neutral water
Mg(OH)2, CaCO3- neutralise stomach acid, form water