Group 2

Question 1

Atomic radius

Answer 1

Atomic radius increases down the group, more shells of electrons make atom bigger

Question 2

Melting point

Answer 2

Decreases. Metallic bonding decreases, atomic size increases, distance between ions increases

Question 3

Ionisation energy

Answer 3

First and second decrease down the group. Outer electrons more shielded from attraction of nucleus

Question 4

Reactivity

Answer 4

Increases down group as atomic radius increases, nuclear attraction decreases

Question 5

Reactions with oxygen

Answer 5

Will burn in oxygen. Mg burns with bright white flame

Question 6

Reaction with water

Answer 6

Mg burns in Stram to produce MgO and hydrogen gas
Mg reacts with warm water producing Mg(OH)2
Other react with cold water with vigour down the group to form hydroxides

Question 7

Reactions w water pt2

Answer 7

Hydroxides produced make water alkaline:
Observed fizzing,metal dissolving, solution heating up, Ca produced a white precipitate

Question 8

Reaction with acid

Answer 8

React with increasing vigour down the ground forming a salt and hydrogen

Question 9

Action of water on oxides of elements in group 2

Answer 9

React with water to form hydroxides, weakly alkaline eg Mg(OH)2 pH9
Ca(OH)2 pH 12

Question 10

Ca(OH)2

Answer 10

Used in agriculture to neutralise acid soils
Equation: CaO + H2O forms Ca(OH)2

Question 11

Mg(OH)2

Answer 11

Treating indigestion, neutralise excess acid in stomach as well as CaCO3