Organics 1 (crude oil and fractional distillation only) - 4th

Question 1

what is crude oil?

Answer 1

• a mixture of hydrocarbons, compounds of hydrogen (H) and carbon (C) only
• the different hydrocarbons in crude oil come in a huge variety of shapes and sizes, which results in crude oil boiling over a very large range of temperatures

Question 2

what is each fraction of crude oil?

Answer 2

• a mixture of similar hydrocarbons with similar boiling points

Question 3

why do we need to separate crude oil?

Answer 3

• most of the hydrocarbons are useful, but often for very different purposes
• this means we need to separate the oil into fractions which contain similarly used molecules.

Question 4

what happens to the fractions of crude oil as the boiling points increase?

Answer 4

• the fractions get darker in colour
• the fractions get more viscous (like treacle)

Question 5

what happens to the fractions of crude oil as the boiling points increase?

Answer 5

• the fractions get darker in colour
• the fractions get more viscous (like treacle)

Question 6

what is the boiling point, molecular mass, colour, viscosity and use of refinery gases?

Answer 6

• low BP
• low molecular mass
• light colour
• low viscosity
• used for fuel for home cooking

Question 7

what is the use of gasoline?

Answer 7

• used for fuel for cars

Question 8

what is the use of kerosene ?

Answer 8

• used for fuel for aircraft

Question 9

what is the use of diesel?

Answer 9

• used for fuel for trains

Question 10

what is the use of fuel oil?

Answer 10

• fuel for ships

Question 11

what is the boiling point, molecular mass, colour, viscosity and use of bitumen?

Answer 11

• high BP
• high molecular mass
• dark colour
• high viscosity
• used for making roads

Question 12

how are each of the fractions separated from crude oil?

Answer 12

• by fractional distillation
• done industrially on a large scale

Question 13

how does fractional distillation work?

Answer 13

• fractionating column is hotter at the bottom and colder at the top
  onenote chemistry rev pic
  THIS IS HOW IT WORKS:
• heated crude oil vapours enter the column

Question 14

what is the order of each of the fractions from lowest to highest BP/order of fractional distillation?

Answer 14

• refinery gases
• gasoline
• kerosene
• diesel
• fuel oil
• bitumen

Question 15

what are fractions?

Answer 15

• mixtures containing the hydrocarbons that boil in a particular temperature range
• for example, kerosene contains hydrocarbons that boil between 250 degrees and 350 degrees.