Group 2

Question 1

What happens when a group (II) metal reacts with water?

Answer 1

The metal atom loses electrons and becomes a 2+ metal ion

Question 2

Elements become less reactive as you go down a group. True or false

Answer 2

False - becomes more reactive because the atoms become larger so the distance between the nucleus and outer e- is greater

Question 3

What does a more vigorous reaction mean in terms of collisions?

Answer 3

More (successful) collisions in a given time

Question 4

When Mg reacts with H2O what two different products could be made? What is the speed of their respective reactions

Answer 4

Mg(OH)2 - v slow

Or

MgO - fast

Question 5

What are the 2 trends in solubility for group 2 hydroxides

Answer 5

1) Solubility increases down the group
2) the strength of the hydroxide as a base increases down the group because there are more hydroxide ions in the solution

Question 6

When NaOH is added to MgCl2
What is produced?

When NaOH is added to BaCl2 what is produced?

Answer 6

A white precipitate of Mg(OH)2

No precipitate as Ba(OH)2 is soluble in water

Question 7

What is the test for hydroxide ions

Answer 7

MgCl2 solution is added and a white precipitate of Mg(OH)2 is formed

Question 8

What is he test for Mg2+ ions

Answer 8

NaOH is added and a white precipitate of Mg(OH)2 is formed

Question 9

What is the trend in solubility of group 2 sulphates

Answer 9

Solubility decreases down the group

Question 10

What is used to test for sulphate ions

Why

Answer 10

Acidified barium chloride

Barium sulphate is insoluble so a white precipitate is produced

Question 11

What acids can and cannot be used to acidity a solution containing barium ions

Answer 11

Can: HCl or HNO3 to remove carbonate ions

Cannot: H2SO4 as it contains sulphate ions so a white precipitate of BaSO4 would form

Question 12

How do you test for barium ions

Answer 12

Add sulphuric acid and a white precipitate of BaSO4 is formed

Question 13

Test for sulphate ions

Answer 13

Add Acidified BaCl2

A white precipitate of BaSO4 is formed

Question 14

Name a use of Mg(OH)2

Answer 14

Medicine to treat indigestion

To neutralise excess stomach acid

Question 15

Name a use of Ca(OH)2

Answer 15

Used in agriculture to neutralise acidity in soils

Question 16

Use of BaSO4

Why is it not dangerous despite being poisonous

Answer 16

Medicine in X Rays to examine oesophagus, stomach and intestine. It coats them in a material that cannot be absorbed so unhealthy areas can clearly be seen

It is insoluble so cant be absorbed by the body

Question 17

How is titanium extracted

Answer 17

Reducing titanium chloride by a more reactive metallic

Question 18

How is TiO2 converted to titanium(IV) chloride

What is the next step in the extraction

Answer 18

Using chlorine and coke at 900 degrees C

Titanium chloride is a liquid which fumes in moist air and is purifies by fractional distillation in argon

Question 19

Equation for converting TiO2 into TiCl4

Answer 19

TiO2(s)+2Cl2(g)+2C(s)
—->
TiCl4(g) + 2CO(g)

Question 20

How is Mg uses in the extraction of titanium

Answer 20

As a reducing agent

It is heated with the titanium Chloride in a crucible in argon at 600 degrees C

Question 21

Why is an atmosphere of argon used to extract Titanium

Answer 21

To prevent oxidation

Question 22

Equation for reduction of titanium chloride

Answer 22

TiCl4(g) + 2Mg(l) —>

Ti(s)+2MgCl2(l)

Question 23

What is flue gas desulphurization

Answer 23

The removal of SO2 from the gases emitted by fossil fuel power plants and other SO2 emitting processes

Question 24

What is used to remove SO2?

Why these compounds?

Answer 24

CaO or CaCO3

To neutralise the SO2 as it is an acidic gas

Question 25

What does flue gas desulphurisation prevent

Answer 25

The release of SO2 into the atmosphere which would cause acid rain