Fuels

Question 1

what is crude oil?

Answer 1

a fossil fuel that is formed over millions of years ago from the remains of marine organisms

Question 2

what is a hydrocarbon?

Answer 2

a compound that is made up of only hydrogens and carbons

Question 3

what is a finite resource?

Answer 3

a resource that is no longer being made or being made extremely slowly

Question 4

what is feedstock

Answer 4

the starting material for an industrial process

Question 5

why is fractional distillation for fuels?

Answer 5

used to separate crude oil into simpler more useful mixtures by using their boiling point

Question 6

how is fractional distillation used to separate crude oil?

Answer 6

• the crude oil is heated to evaporate
• vapours rise in the fractionating column
• the column has a temperature gradient, hot at the bottom and cool at the top
• because of this each fraction condenses where it becomes cool enough and is piped out of the column

Question 7

how does boiling point change the fuels get larger

Answer 7

increase

Question 8

how does the ease of ignition change the fuels get larger?

Answer 8

less flammable more difficult to ignite

Question 9

how does viscosity change the fuels get larger

Answer 9

they get more viscous/thicker

Question 10

what are the 6 crude oil fractions?

Answer 10

gases, petrol, kerosene, diesel oil, fuel oil, bitumen

Question 11

what are the uses of fuel gas?

Answer 11

domestic heating and cooking

Question 12

what are the uses of petrol?

Answer 12

fuel for cars

Question 13

what are the uses of kerosene?

Answer 13

fuel for aircraft

Question 14

what are the uses of diesel oil?

Answer 14

some cars and trains

Question 15

what are the uses of fuel oil?

Answer 15

fuel for large ships and some power stations

Question 16

what are the uses of bitumen?

Answer 16

surfacing roads and roofs

Question 17

when does incomplete combustion happen

Answer 17

when there is not enough oxygen

Question 18

what are the products of complete combustion?

Answer 18

carbon dioxide and water

Question 19

what are the products of complete incombustion?

Answer 19

carbon dioxide, water, carbon monoxide and soot (carbon)

Question 20

which gives out more heat, complete or incomplete combustion

Answer 20

complete combustion

Question 21

why is carbon monoxide dangerous?

Answer 21

it is a colourless and odourless gas that can attach to blood instead of oxygen, which reduces the amount of oxygen that is sent around the body

Question 22

why is soot dangerous?

Answer 22

tiny soot particles can be breathed in, which may lead to lung disease

Question 23

what is a non-renewable fuel?

Answer 23

a fuel that is used up faster than it is produced

Question 24

what are the 3 features of a good fuel?

Answer 24

nurn easily
not produce soot
release a lot of energy
easy to store and transport

Question 25

what is the product of hydrogen combustion?

Answer 25

water

Question 26

what are 4 positives of petrol?

Answer 26

burns easily
does not produce ash
releases more energy than coal or wood
is a liquid so it is easy to store and transport

Question 27

what are 2 negatives of petrol?

Answer 27

produces carbon dioxide - bad for the environment
is a finite source

Question 28

what are the 4 positives of hydrogen as fuel?

Answer 28

burns easily
does not produce ash or smoke
only produces water
releases more energy than petrol per Kg

Question 29

what are the 2 negatives of hydrogen as fuel?

Answer 29

is a gas so is hard to store (high pressures needed)
filling station will need to be adapted (new infrastructure)

Question 30

what is cracking?

Answer 30

a process in which you break down larger alkanes into more useful alkanes and alkenes

Question 31

why must we crack fuels?

Answer 31

some larger alkanes such as bitumen are in greater supply than their demand. cracking will convert these longer alkanes into smaller more useful alkanes such as petrol, which is in greater demand than that can be supplied by fractional distillation alone