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Flashcards in Chemistry In Industry Deck (35):
1

How are most metals found?

in their ores

in the Earth's crust combined with other elecments

the individual compounds are called minerals

2

What is a metal ore?

a metal ore is a compound that contains enough the mineral for it to be economically viable to extract some metal

3

What is the price of a metal affected by>

how common the ore is

how difficult it is so extract the metal from its ore

4

There is a limited/unlimited amount of metal ores - they are ... resources

There is a limited amount of metal ores - they are finite resources

5

The more reactive a metal is, the easier/harder it is to extract it from its compound

The more reactive a metal is, the harder it is to extract it from its compound

6

What are native metals?

very unreactive metals, such as godl, that exist naturally as the uncombined element (you just have to find them and dig them up)

silver and copper are also sometimes found native - although much more rarely

7

What do metals often have to be separated from?

their oxides

8

How to metals form oxides?

lots of metalls, like iron and aluminium, react with oxygen to form oxides

these oxides are often the ores that the metals need to be extracted from

9

What is the name of the reaction that separates a metal from the oxygen it its oxide?

a reduction reaction

e.g. 2CuO + C → 2Cu + CO2

10

The most common type of reduction reaction uses ... as a reducing agent to separate the oxygen from the metal

The most common type of reduction reaction uses carbon as a reducing agent to separate the oxygen from the metal

11

Metals exist as positive ions in their ... . To produce the metal you would have to ... . This is called ...

Metals exist as positive ions in their ionic compounds . To produce the metal you would have to add electrons to the positive ion . This is called called reduction

12

What is 'roasting'?

converting a metal compound into an oxide by heating in air

13

What are the two main economic factors to take into account when deciding on the method of reducing an ore to the metal?

the cost of energy

the cost of the reducing agent

14

How are some metals, such as titanium, extracted? Is this expensive? Why?

by heating thecompound with a more reactive metal

this is expensive, because the more reactive metal itself will have to be extractedby an expensive process first

15

How are metals below carbon in the reactivity series extracted? Is this expensive? Why?

they are extracted by a reduction reaction by heating the metal ore with carbon or carbon monoxide

this is the cheapest method of reducing the ore

carbon is cheap and can also be used as the source of heat

16

What is the order of the reactivity series?

potassium

sodium

calcium

magnesium

aluminium

carbon

zinc

iron

tin

lead

hydrogen

copper

silver

gold

platinum

17

How do you remember the order of the reactivity series?

polly

smith

cut

my

amazingly

cool

zebra

into

two

lamp

hamburger

chops

creating

super

gravy

platas

18

Explain how are metals below carbon in the reactivity series are extracted by heating the ore with carbon or carbon monoxide

more reactive elements form compounds more readily

carbon is more reactive than, for example, iron, so carbon displaces the oxygen from iron oxide

carbon can only remove the oxygen away from metals which are less reactive than carbon itself

19

Ores of metals higher in the reactivity series than zinc can't be reduced using carbon at ...

Ores of metals higher in the reactivity series than zinc can't be reduced using carbon at reasonable temperatures

20

How are metals above carbon in the reactivity series extracted? Is this expensive?

by electrolysis

the large amounts of electricity involved make this an expensive process so a metal like aluminium is much more expensive than one like iron

21

Very reactive metals form very stable/unstable ores - it's easy/difficult to get the metal out of its compound

Very reactive metals form very stable ores - it's difficult to get the metal out of its compound

22

What can burning fuels produce? Give three examples

pollutants

e.g. carbon monoxide, nitrogen oxides and sulphur dioxide

23

How is carbon monoxide (CO) produced?

when hydrocarbon fuels (e.g. petrol or diesel in car engines, or gas in central heating) are burnt without enough oxygen - incomplete combustion

24

Why is carbon monoxide poisonous? What can this lead to?

it can stop your blood cells doing their proper job of carrying oxygen around the body as it combines with the haemoglobin in blood cells, meaning the blood can carry less oxygen

a lack of oxygen in the blood can lead to fainting, a coma or even death

25

When are sulphur dioxide (SO2) and nitrogen oxides released?

when fossil fuels are burned

26

How is sulphur dioxide formed?

sulphur impurities in fossil fuels

27

How are nitrogen oxides formed?

when the temperature is high enough for the nitrogen and oxyegn in the air to react

this often happens in car engines

28

What are two examples of nitrogen oxides?

nitrogen monoxide (NO)
nitrogen dioxide (NO2)

29

All rain is ... acidic because ...

All rain is slightly acidic because carbon dioxide in the air reacts with water to produce a slightly acidic solution:

carbon dioxide + water → carbonic acid

CO2 (g) + H2(l) → H2CO3 (aq)

30

What happens when sulphur dioxide mixes with clouds?

when sulphur dioxide mixes with clouds it forms dilute sulphuric acid, which is much more acidic:

sulphir dioxide + oxygen +water → sulphuric acid

2SO2 (g) + O2 (g) + 2H2(l) → 2H2SO4 (aq)

31

What can nitrogen oxides form in clouds?

nitric acid

32

What is acid rain caused by?

sulphur dioxide and nitrogen oxides mixing with clouds

rain that falls from these clouds is called acid rain

33

What does acid rain do to lakes?

acid rain causes lakes to become acidic and many plants and animals die as a result

34

What does acid rain do to trees?

acid rain kills trees

35

What does acid rain do to buildings and statues?

acid rain can damage limestone buildings and ruins stone statues