Module 4 - Core Organic Chemistry

Question 1

What is the definition for a hydrocarbon?

Answer 1

A compound consisting of hydrogen and carbon only

Question 2

What is a homologous series?

Answer 2

A family of compounds that have similar chemical properties

They differ by the addition of a -CH- group

Question 3

What is an alicyclic hydrocarbon?

Answer 3

Where carbon atoms are joined to each other in ring(cyclic) structures

Question 4

What is the difference between a saturated and an unsaturated hydrocarbon?

Answer 4

Unsaturated - contains a double or triple bond

Saturated - contains only single bonds

Question 5

What is an aliphatic hydrocarbon?

Answer 5

Where carbon atoms are joined to each other in unbranched(straight) ir branched chains

Question 6

What is an alkene?

Answer 6

Functional Group - NH2n
Contains at least one double C=C bond
So is unsaturated
Aliphatic hydrocarbon

Question 7

What is an alkyne?

Answer 7

Functional Group - CnH2n-2

Contains at least one triple Carbon - Carbon Bond

Question 8

What is an aromatic hydrocarbon?

Answer 8

Where some or all of the carbon atoms are found in a benzene ring(C6H6)

Question 9

Name and give equations for the first 4 alkanes

Answer 9

Methane - CH4
Ethane - C2H6
Propane - C3H8
Butane - C4 H10

Question 10

Properties of alkanes

Answer 10

Hydrocarbon
Flammable
Saturated(only single bonds)
Don’t react with bromine water
More viscous as chain length increases

Question 11

How to distinguish between saturated and unsaturated hydrocarbons

Answer 11

React substance with bromine water
Saturated(single bonds) - doesn’t react with bromine water
Solution stays colourless
Unsaturated(double or triple bonds) - reacts with bromine water
Solution turns orange

Question 12

What is a functional group?

Answer 12

A group of atoms responsible for the characteristic reactions of a compound

Question 13

Give the functional group of an alkane

Answer 13

CnH2n+2

Question 14

stage 1 H2 + anthraquinone → anthraquinol
stage 2 O2 + anthraquinol → H2O2 + anthraquinone

Explain the advantages of the manufacture of H2O2 from hydrogen and oxygen.

Answer 14

• 100% atom economy/higher atom economy
• No toxic/poisonous byproducts formed during reaction
• Anthraquinone is regenerated - acts as a catalyst for the reaction
• Oxygen comes form air - is readily available to be used for the reaction

Question 15

Explain why the straight chain isomer of C10H22 is converted by the petroleum industry into its branched chain isomers.

Answer 15

• Branched chain isomers are easier to combust/have more efficient combustion

Question 16

Explain why the straight chain isomer of C10H22 has a higher boiling point than any of its branched chain structural isomers.

Answer 16

• Less branching
• More surface contact
• More/Greater London Forces
• So more energy required to break the strong/stronger London Forces between molecules

Question 17

Butan-2-ol and 2-methylpropan-2-ol are structural isomers.

i) What is meant by the term structural isomer? (1 Mark

Answer 17

• Versions of a compound containing the same molecular formula, but different structural formula

Question 18

Atom economy def

Answer 18

• The molecular masses of the desired product ÷ sum of molecular masses of all products
  × 100