Extracting metals and Equilibria

Question 1

What is Oxidation?

Answer 1

The addition of oxygen and loss of electrons.

Question 2

What is Reduction?

Answer 2

The reduction of oxygen and gain of electrons.

Question 3

What do Combustion reactions involve?

Answer 3

Oxidation.

Question 4

What is Reactivity?

Answer 4

How easily positive ions form or how easily outer electrons are lost.

Question 5

What Group in the periodic table has the most reactive metals?

Answer 5

Group 1 metals.

Question 6

What happens when you react metals with acids?

Answer 6

You produce Salt and Hydrogen.

Question 7

Most reactive metals produce the most…

Answer 7

Heat.

Question 8

How do we compare the reactivity of the metals fairly?

Answer 8

By ensuring the metals have the same mass/surface area and that we use the same type and concentration each time.

Question 9

What happens when you react metals with water?

Answer 9

You produce Metal hydroxide + Hydrogen.

Question 10

What is a Displacement Reaction?

Answer 10

When a more reactive metal displaces a less reactive metal in a compound.

Question 11

When metal reacts with acid, the more reactive the metal is…

Answer 11

the faster the reaction with the acid will go.

Question 12

When very reactive metals react with acid what happens?

Answer 12

It will fizz vigorously. E.g. Magnesium

Question 13

When less active metals react with acid what happens?

Answer 13

It will bubble a little bit. E.g. Zinc.

Question 14

When unreactive metals are put in acid what happens?

Answer 14

It will not react at all.

Question 15

How can you test for hydrogen?

Answer 15

Using a light splint.

Question 16

The louder the squeaky pop… (lighted splint test)

Answer 16

The more hydrogen has been made in the time period and the more reactive the metal is.

Question 17

What is the speed of reaction also indicated by?

Answer 17

The rate at which the bubbles of hydrogen are given off - the faster the bubbles form, the faster the reaction and the more reactive metal.

Question 18

What is a metal ore?

Answer 18

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

Question 19

What is the ore in the metal ore?

Answer 19

An oxide.

Question 20

Where are most of the metals that we use found?

Answer 20

Their ores in the Earth’s crust.

Question 21

Extracting metals from its ore chemically by reduction using carbon only work on metals…

Answer 21

Less reactive than carbon.

Question 22

When an ore is reduced…

Answer 22

Oxygen is removed from it.

Question 23

Metal oxide + Carbon ->…

Answer 23

Pure metal + Carbon dioxide

Question 24

If the metal is more reactive than carbon how can it be extracted?

Answer 24

Using electrolysis of molten compounds.

Question 25

In order to run electrolysis to extract materials from their ores, you need...

Answer 25

Large amounts of electricity.

Question 26

Explain why metals lower down the reactivity series (less reactive than carbon) are cheaper to extract than those higher up the reactivity series.

Answer 26

In electrolysis, large amounts of electricity is needed which is expensive and there also additional costs with melting or dissolving the metal ore. In comparison, extracting metals using reduction with carbon, is much cheaper. Carbon is cheap and also acts as a fuel to provide the heat needed for the reduction reaction to happen.

Question 27

What is Bioleaching?

Answer 27

Uses bacteria to separate metals from their ores.

Question 28

What is Phytoextraction?

Answer 28

Involves growing plants in soil that contains metal compounds.

Question 29

What does Recycling metals save?

Answer 29

Energy.

Question 30

How does recycling protect the environment?

Answer 30

Mines are damaging to the environment and destroy habitats. Recycling would mean we wouldn't have to use so many mines. Also cut down the amount of rubbish that gets sent to landfill. Landfill takes up space and pollutes the surrounding.

Question 31

How is Recycling metals good economically?

Answer 31

Recycling is a massive industry and can create lots of jobs.

Question 32

What does the Life Cycle Assessment do?

Answer 32

Looks at each stage of the life of a product. From making the product, manufacturing it, using it and then disposing it.

Question 33

What is a Reversible reaction?

Answer 33

One where the products can react with each other to produce the original reactants.

Question 34

What happens during the Haber process?

Answer 34

Nitrogen and hydrogen react to form Ammonia.

Question 35

At what temperature is the Haber process carried out?

Answer 35

450 degrees celsius.

Question 36

At what pressure is the Haber process carried out at?

Answer 36

A pressure of 200 atmospheres and an iron catalyst.

Question 37

If there's a change in concentration, pressure or temperature in a reversible reaction...

Answer 37

The equilibrium position will move to help counteract that change.

Question 38

If you decrease the temperature...

Answer 38

The equilibrium will move in the exothermic direction to produce more heat.

Question 39

If you increase the temperature...

Answer 39

The equilibrium will move in the endothermic direction to absorb extra heat.

Question 40

If you increase the pressure...

Answer 40

The equilibrium will move towards the side that has fewer molecules of gas to reduce pressure.

Question 41

If you decrease the pressure...

Answer 41

The equilibrium will move towards the side that has more molecules of gas to increase pressure.

Question 42

If you increase the concentration of the reactants...

Answer 42

The equilibrium will move to the right to use up the reactants.

Question 43

If you increase the concentration of the products...

Answer 43

The equilibrium will move to the left to use up the products.

Question 44

What will decreasing the concentration do?

Answer 44

Have opposite effect.