Carbon Chemistry

Question 1

What are the properties of cycloalkanes?

Answer 1

• They are saturated hydrocarbons ( C-C single bonds)
• Insoluble
• Used for fuels and solvents

Question 2

What are hydrocarbons?

Answer 2

Compounds that contain hydrogen and carbon only.

Question 3

What is the lowest number of carbon atoms possible in a cycloalkane?

Answer 3

3 carbon atoms, called cyclopropane

Question 4

What is a homologous series?

Answer 4

A family of chemicals that have similar chemical properties and the same general formula. (eg: alkanes, alkenes, cycloalkanes, alcohols, carboxylic acids).

Question 5

What are alkanes?

Answer 5

Alkanes are a homologous series that contain carbon atoms joined together by single bonds, which are surrounded by hydrogen. They are hydrocarbons.

Question 6

What is the general formula of alkanes?

Answer 6

CnH2n+2

Question 7

What is the general formula for cycloalkanes?

Answer 7

CₙH₂ₙ

Question 8

Are alkanes insoluble?

Answer 8

Yes

Question 9

What is an unsaturated bond?

Answer 9

C - C single bond.

Question 10

Name the first eight members of the alkane series.

Answer 10

Methane CH₄, ethane C₂H₆, propane C₃H₈, butane C₄H₁₀, pentane C₅H₁₂, hexane C₆H₁₄, heptane C₇H₁₆, octane C₈H₁₈.

Question 11

In homologous series’, what happens to the melting / boiling point as the size of the molecule increases?

Answer 11

As the size of the molecule increases, the melting / boiling point increases.

Question 12

What are isomers?

Answer 12

They have the same molecular formula but a different structural formula.

(eg: butane C₄H₁₀ and 2-methylpropane C₄H₁₀)

Question 13

What are the properties of alkenes?

Answer 13

• Unsaturated hydrocarbons (contains at least one double bond between carbon atoms)
• Names end in -ene
• Double bond can be anywhere in the chain
• Insoluble in water
• Can be used to make polymers and alcohols

Question 14

What is the general formula of the alkenes?

Answer 14

CₙH₂ₙ

Question 15

How do you name branched alkanes?

Answer 15

1) Draw out full structural formula.

2) Look for longest chain of carbon atoms.

3) Which side is the branch closest to and call the starting carbon C₁.

4) Give the other carbons in the chain positions.

5) See what position the branch is on and give a prefix.

If there is 1 C in the branch, methyl
2 C in the branch, ethyl etc.

Question 16

What is the name of this branched alkane: CH₃CH(CH₃)CH₂CH(CH₃)CH₂CH₃.

Answer 16

2, 4 - dimethylhexane

Question 17

Name the first 3 members of the cycloalkanes series

Answer 17

Cyclopropane - C₃H₆
Cyclobutane - C₄H₈
Cyclopropane - C₅H₁₀

Question 18

How do you name alkenes?

Answer 18

1) Look for the longest continuous chain - name it after the corresponding alkane, ie: meth = 1, eth = 2 etc.

2) Give the double bond a position, eg: position 2

3) The position of the double bond goes inside the name, eg: pent-2-ene

4) If a branch is present, give it a position from the side the double bond is closest to.