Alkanes

Question 1

Alkanes

Answer 1

They are saturated carbons with the general formula:

           CnH2n+2

Question 2

Fractional distillation

Answer 2

• crude oil is heated and vaporised
• the vaporised oil enters the column and rises
• the fractions have different boiling points
• the temperature gradient is cooler at the top and hotter at the bottom

Question 3

Cracking

Answer 3

Heavier fractions can be creaked into lighter fractions

Question 4

What are the two types of cracking

Answer 4

1) thermal cracking
2) catalytic cracking

Question 5

Thermal cracking

Answer 5

CONDITIONS:
- high temperature
- high pressure

Question 6

Catalytic cracking

Answer 6

CONDITIONS:
- high temperature
- moderate pressure
- zeolite catalyst is used

Question 7

Zeolite catalysts

Answer 7

Used to help lower the temperature needed for cracking to occur

Question 8

Complete combustion

Answer 8

Excess oxygen alkanes will burn with complete combustion

Produces are H2O and CO2

Question 9

Incomplete combustion

Answer 9

When there is a limited amour of oxygen

Produces: CO (which is very toxic) and C ( producing a sooty flame)