3.1.2 Group 2

Question 1

What is the trend in the first ionisation energies in Group 2 and how does this explain their trend in reactivity ?

Answer 1

Decreases down the group as increasing atomic radius and shielding this means it is easier to loose the outer electrons so reactivity increases down group

Question 2

Group 2 Metal + Water >

Answer 2

Metal Hydroxide + Hydrogen

Question 3

Group 2 Metal + Oxygen >

Answer 3

Metal Oxide

Question 4

Group 2 Metal + Dilute Acid >

Answer 4

Salt + Hydrogen

Question 5

This question is about reactions and uses of the weak acids methanoic acid, HCOOH, and
ethanoic acid, CH3COOH.
A student adds magnesium metal to an aqueous solution of ethanoic acid, CH3COOH.
A redox reaction takes place.
Write the overall equation for this reaction and explain, in terms of oxidation numbers, which
element has been oxidised and which element has been reduced

Answer 5

Mg + 2CH3COOH → (CH3COO)2Mg +
H2
Oxidation: Mg from 0 to +2
Reduction: H from +1 to 0

Question 6

This question is about barium hydroxide.
A student plans to prepare a solution of Ba(OH)2 from barium by two different reaction routes.
Outline 2 reaction routes for preparing a solution of Ba(OH)2 from barium in the laboratory.
Include relevant equations

Answer 6

Reactant:
Add water (to Ba) OR H2O in equation
Balanced equation:
Ba + 2H2O → Ba(OH)2 + H2
Route 2
Balanced equation with O2
2Ba + O2 → 2BaO
Balanced equation with H2O
BaO + H2O → Ba(OH)2