Section 4 - Extracting Metals & Equilibria

Question 1

What does the reactivity series show?

Answer 1

How easily metals are oxidised.

Question 2

Which two non-metals can be included on the reactivity series?

Answer 2

Carbon and hydrogen.

Question 3

What is the trend with position on the reactivity series and reactivity?

Answer 3

The higher an element is positioned on the reactivity series, the more easily it is oxidised.

Question 4

What happens when a reactive metal is placed in dilute hydrochloric acid?

Answer 4

It reacts quickly and vigorously releasing hydrogen gas.

Question 5

What happens in a displacement reaction?

Answer 5

The more reactive element takes the place of the less reactive one.

Question 6

What is an ore?

Answer 6

A rock which contains enough metal to make it economically worthwhile extracting the metal from it.

Question 7

What ways can metals be extracted?

Answer 7

With carbon
Electrolysis
Biologically

Question 8

How can metals be extracted with carbon?

Answer 8

Metals lower than carbon on the reactivity series can be extracted by reducing them with carbon, this removes the oxygen from the ore.

Question 9

How are metals extracted using electrolysis?

Answer 9

Any metal higher than carbon on the reactivity series must be extracted using electrolysis, this is done by melting the ore and passing a current through it, this draws the metal towards the cathode and the non-metals at the anode.

Question 10

What is the trend between a metal’s position on the reactivity series and the cost of extraction?

Answer 10

The higher a metal is on the reactivity series, the more it will cost to extract.

Question 11

What are two biological methods of extracting metals?

Answer 11

Bioleaching and phytoextraction.

Question 12

What is bioleaching?

Answer 12

Using bacteria to separate metals from their ores.

Question 13

What is phytoextraction?

Answer 13

Growing plants in soil that contains metal compounds, the plants cannot use the metals so they build up in the leaves, plants are then harvested and burned, the ash contains lots of metal compounds which can be extracted further.

Question 14

What does recycling do?

Answer 14

Conserves resources and energy as well as saves the environment.

Question 15

How does recycling benefit us?

Answer 15

It is a large industry that creates a lot of jobs, it is less expensive than extracting from scratch and is much cheaper for us.

Question 16

What is a life cycle assessment?

Answer 16

An assessment that looks at each stage of a product’s life, and works out the potential environmental impact of each stage.

Question 17

What is a reversible reaction?

Answer 17

A reaction where the products can react together to form the original reactants.

Question 18

What is dynamic equilibrium?

Answer 18

When the forward reaction of a reversible reaction is equal to the reverse reaction.

Question 19

What factors can change the position of equilibrium in reversible reactions?

Answer 19

Temperature, pressure and concentration.

Question 20

What is Le Chatlier’s principle?

Answer 20

The position of dynamic equilibrium moves to minimise any changes you make.

Question 21

How does Le Chatlier’s principle apply to temperature?

Answer 21

All reactions are exothermic in one direction and endothermic in the other, if temperature increases, equilibrium shifts in the endothermic direction to absorb the extra heat.

Question 22

How does Le Chatlier’s principle apply to pressure?

Answer 22

If pressure increases, equilibrium shifts in the direction with fewer moles of gas.

Question 23

How does Le Chatlier’s principle apply to concentration?

Answer 23

If the concentration of products increases,equilibrium shifts to create more products and vice versa.
Decreasing concentration has the opposite effect.