9.4 Crude Oil and Fuels (Cracking Hydrocarbons)

Question 1

Cracking is …

Answer 1

Breaking down of large useless hydrocarbon chains into smaller more useful molecules.

Question 2

What is an alkene?

Answer 2

Unsaturated hydrocarbons with at least one carbon to carbon double bond (C=C) with the general formula C_nH_2n

Question 3

Cracking decane, C₁₀H₂₂ produces ethene and hexane. Write a balanced chemical equation for the reaction.

Answer 3

C₁₀H₂₂ —>
2 C₂H₄ + C₆H₁₄

Question 4

Cracking hydrocarbons can give multiple alkenes. How many short chain alkanes can be produced from cracking an alkane?

Answer 4

Only one due to a limited number of hydrogen atoms.

Question 5

In organic chemistry, what is the meaning of unsaturated?

Answer 5

Organic molecule containing carbon-carbon double C=C ( or triple) bonds.

Question 6

What is the test for unsaturation?

Answer 6

Bubble through bromine water which goes form orange to colourless.

Question 7

Name a catalyst used in cracking alkanes.

Answer 7

Any one from:
- aluminium oxide (alumina)
- silicon oxide
- zeolite

Question 8

What is the meaning of functional group?

Answer 8

An atom or group of atoms that gives a molecule it reactivity.