cracking and alkenes

Question 1

What is cracking?

Answer 1

cracking is a reaction in which larger saturated hydrocarbon molecules are broke down into smaller, more useful hydrocarbon molecules, some of which are unsaturated

Question 2

What are the two methods of cracking and what are the necessary conditions?

Answer 2

steam cracking
- 800 degrees Celsius / no catalyst

catalytic cracking
- 550 degrees Celsius / zeolite catalyst

Question 3

Which are more reactive : alkanes or alkenes?

Answer 3

alkenes

Question 4

What is the test for alkenes?

Answer 4

bromine water; orange to colourless

Question 5

What type of bond do all alkenes contain?

Answer 5

C = C

double bonds

Question 6

What is the general formula for the homologous series of alkenes?

Answer 6

CnH2n

Question 7

Why are alkenes unsaturated?

Answer 7

they contain two fewer hydrogen atoms than the alkane with the same number of carbons

Question 8

What are the first four members of the homologous series of alkenes?

Answer 8

ethene, propene, butane, pentene

Question 9

Draw the structural formula of butane C4H8

Answer 9

The double bond could be between any two carbons, but make sure each carbon has four bonds

Question 10

What alcohol is produced when water reacts with butane?

Answer 10

Butanol

Question 11

What chemical is produced when bromine reacts with pentene?

Answer 11

bromopentane