fuels and earth science

Question 1

what is crude oil

Answer 1

it is our main source of hydrocarbons

Question 2

how are different hydrocarbons separated in crude oil

Answer 2

fractional distillation

Question 3

what is petrol used for

Answer 3

fuel for cars

Question 4

what is kerosene used for

Answer 4

fuel for aircraft

Question 5

what is diesel used for

Answer 5

fuel for some cars and larger vehicles

Question 6

what is fuel oil used for

Answer 6

fuel for ships

Question 7

what is bitumen used for

Answer 7

used to make roads

Question 8

what are some properties of short hydrocarbons

Answer 8

-easy to ignite
-lower relative melting and boiling point

Question 9

what are some properties of long hydrocarbons

Answer 9

-hard to ignite
-higher relative melting and boiling points

Question 10

what is complete combustion

Answer 10

are reaction that only forms carbon dioxide and water

Question 11

when does incomplete combustion happen

Answer 11

when there is a limited supply of oxygen

Question 12

what products does incomplete reaction form

Answer 12

carbon monoxide and carbon in a form of soot
and water

Question 13

why is carbon monoxide toxic

Answer 13

it can combine with red blood cells and stop them from carrying oxygen

Question 14

why is sulfur dioxide a pollutant

Answer 14

they can mix with clouds to form sulfuric acid. this will then form as acid rain

Question 15

why are nitrogen oxides pollutants

Answer 15

they can contribute to acid rain and at ground level, it can cause photochemical smog

Question 16

what are some pros of using hydrogen as fuel

Answer 16

no pollutants released

Question 17

what are some cons of using hydrogen as fuel

Answer 17

you need a special expensive engine to use and it is also hard to store

Question 18

what is cracking

Answer 18

it is the splitting up of long chain hydrocarbons

Question 19

what is the optimum temperature for cracking

Answer 19

400celsius-700

Question 20

what is the optimum pressure for cracking

Answer 20

70atm

Question 21

what is the catalyst used in cracking

Answer 21

aluminium oxide

Question 22

how does cracking help supply and demand

Answer 22

shorter hydrocarbons are in higher demand and there is an excess of long chain hydrocarbons. the cracking of long chain hydrocarbons means that there is more shorter hydrocarbons available

Question 23

how was our atmosphere formed

Answer 23

• 4.5 billion years ago, the early atmosphere consisted of CO2 and water vapour formed by volcanoes. no O2.
  -4 billion years ago, the earth cooled and water vapour turned into the oceans. CO2 disolved into water.
  -2.4 billion years ago, rocks containing iron oxide starts to form. oxidation suggests an increase of O2. fossils also prove this
  -there are microorganisms called cyanobacteria which use photosynthesis to produce O2
  -a different type of iron oxide forms which needs lots of O2(Fe2O3)
  -oxygen increases until plants evolve

Question 24

explain how the greenhouse effect occurs

Answer 24

-sun gives out radiation
-some of the radiation is absorbed by the earth
-some of it is re-emmited back into space
-greenhouse gasses trap some radiation from leaving, warming up the planet
-the more gases, the warmer the planet