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Question 1

What is the symbol equation for displacement?

Answer 1

Eg copper sulfate + iron ——> iron sulfate + copper.

Question 2

What are lifecycle assessments?

Answer 2

They look at each stage of a life of a product to see the potential environmental impact.

Question 3

What is a mixture?

Answer 3

Two or more elements or compounds not chemically joined together.

Question 4

What is a hydrocarbon?

Answer 4

A compound or molecule made up of hydrogen and carbon only.

Question 5

How can a mixture of alkanes be separated by fractional distillation?

Answer 5

The alkanes/ oil is heated until it turns into gas. The gas enters the fractioning column is heated to make it into vapour. The hydrocarbons will be cool. Longer hydrocarbon chains have high boiling points so they drain out at the bottom where it is very hot. Shorter hydrocarbon chains have lower boiling points so they drain out at the top where it’s cool.

Question 6

What is crude oil and how is it formed?

Answer 6

It is a mixture of lots of different hydrocarbons made from fossil fuels created from remains of dead plants and animals in sedimentary rocks.

Question 7

What is crude oil used for?

Answer 7

It is the main source of hydrocarbon and is used as a raw material to create lots of petro chemicals.

Question 8

Why is crude oil a mixture?

Answer 8

Because it contains lots of different hydrocarbons.

Question 9

How many carbon atoms does methane have?

Answer 9

1

Question 10

How many carbon atoms does ethane have?

Answer 10

2

Question 11

How many carbon atoms does propane have?

Answer 11

3

Question 12

How many carbon atoms does butane have?

Answer 12

4

Question 13

What is thermal decomposition?

Answer 13

The breakdown of a substance or compound by the action of heating it.

Question 14

Why aren’t heavy fractions of crude oil useful?

Answer 14

They have high boiling points and don’t ignite easily.

Question 15

What is cracking an example of?

Answer 15

A thermal decomposition reaction

Question 16

What is steam cracking?

Answer 16

Vapourised heavy hydrocarbons are mixed with steam in a high temperature environment which produces alkanes and alkenes.

Question 17

What is catalytic cracking?

Answer 17

Vaporised heavy hydrocarbons are passed over a hot catalyst to produces alkanes and alkenes.

Question 18

Why is cracking useful?

Answer 18

Smaller molecules are more useful as fuels.

Compounds with larger molecules don’t flow easily.

Compounds with smaller molecules are more In demand.

To make polymers or plastics.

Question 19

When answering a question about cracking..

Answer 19

Include a named alkene or alkane it can produce eg ethene

Question 20

How do you do a cracking equation?

Answer 20

Just make sure they add up.

Question 21

What is the percentage order of gases in the atmosphere?

Answer 21

Nitrogen, oxygen then argon

Question 22

What are the processes which have brought about the changes in the proportions of the gases in the air over billions of years?

Answer 22

Plants have evolved and carry out photosynthesis to take in CO2 and give out oxygen.

Water vapour in the atmosphere condensed due to cooling.

CO2 from the air is trapped in sedimentary rocks. CO2 from the air is dissolved by oceans.

Nitrogen is produced by micro- organisms and builds up because its unreactive.

Question 23

What are environmental problems of carbon dioxide and carbon particles?

Answer 23

Causes global warming

Question 24

What are possible environmental problems of crude oil?

Answer 24

It’s a non-renewable source.

Question 25

What is a possible environmental problem of water?

Answer 25

It’s a non-polluting liquid.

Question 26

How is sulfur dioxide dangerous?

Answer 26

It causes acid rain

Question 27

What colour is the universal indicator of sulfur dioxide?

Answer 27

Red because it’s acidic.

Question 28

Sulfur dioxide is covalent In terms of structure and bonding, explain why sulfur dioxide has a low boiling point.

Answer 28

They are weak forces of attraction between molecules that take little energy to overcome.

Question 29

What can fossil fuels release when they are burned?

Answer 29

They can release harmful chemicals such as sulfur dioxide and various nitrogen oxides.

Question 30

How are nitrogen oxides created?

Answer 30

A reaction between the nitrogen and oxygen in the air which is caused by the heat of the burning. When these gases mix with clouds they form dilute sulfuric acid and dilute nitric acid which causes acid rain.

Question 31

What are the main causes of acid rain?

Answer 31

Power stations and internal combustion engines.

Question 32

What are the effects of acid rain?

Answer 32

It causes lakes to become acidic killing many aquatic plants and animals as a result. It kills trees, damages limestone buildings and makes metal corrode.

Question 33

How can oxides of nitrogen effect the environment?

Answer 33

It can cause photochemical smog which is a type of air pollution caused by sunlight acting on oxides of nitrogen. These oxides combine with oxygen to produce Ozone (O3). Ozone can cause breathing difficulties and headaches.

Question 34

What are the effects of carbon monoxide?

Answer 34

Carbon monoxide can cause the blood to stop carrying oxygen to cells and a lack of oxygen can cause fainting, a coma or death.

Question 35

How are particulates formed?

Answer 35

During incomplete combustion , small pieces of solid called particulates can be released into the atmosphere. They are mainly pieces of carbon called particulate carbon. If they escape into the atmosphere they float but eventually, the fall back to the ground in the form of soot. Particulates reduce air quality and worsen respiratory problems.

Question 36

Why is it difficult to produce models for future climate change?

Answer 36

There are many alternative theories, different variables and they are complex systems to make.

Question 37

How can carbon dioxide maintain temperatures on earth?

Answer 37

The sun gives out electromagnetic radiation. Carbon dioxide/ greenhouse gases allows short wavelength of radiation to pass through the atmosphere to the earth’s surface and carbon dioxide absorbs outgoing long wavelength radiation, which warms the earth.

Question 38

How has human activity increased global air temperature?

Answer 38

Increased burning of fossil fuels causes more carbon dioxide to be released. Deforestation causes more carbon dioxide to be released Use of landfill causes more methane

Question 39

What are the two main steps to treat water from reservoirs and why?

Answer 39

Step 1 : filter to remove solids Step 2: add chlorine to kill microbes.

Question 40

Why is it more difficult to produce drinking water from waste water in lakes?

Answer 40

There is more organic matter and more microbes so it takes a long time to fully sterilise it.

Question 41

Why isn’t distillation used to produce pure water?

Answer 41

It uses a lot of energy

Question 42

How could water be tested to show its pure?

Answer 42

Find the boiling point , it should be a fixed temperature of 100 degrees if it’s impure it will boil at a temperature higher than 100 degrees.

Question 43

What piece of apparatus would be suitable for measuring 25cm cubed of the sea?

Answer 43

Measuring cylinder

Question 44

How can you check if water has been evaporated?

Answer 44

Reheat the evaporating agent and weigh it again, if the mass hasn’t changed, it’s been evaporated.

Question 45

How would you calculate the mass of solid dissolved in sea water?

Answer 45

Subtract the bigger mass from the smaller one then multiply it to what the question asks you.