Organic Chemistry

Question 1

Define General Formula:

Answer 1

An algebraic formula that can describe any member of a family of compounds. e.g. Cn H2n+1 OH

Question 2

Define Empirical Formula:

Answer 2

Simplest whole ration number of atoms of elements in a compound (cancel if possible). eg C₄H₁₀O

Question 3

Define Molecular Formula:

Answer 3

The actual number of atoms of each element in each molecule. eg C₄H₁₀O

Question 4

Define Structural Formula:

Answer 4

Shows the arrangement of atoms carbon by carbon, with the attached hydrogen and functional groups. e.g. CH₃CH₂CH₂CH₂OH.

Question 5

Define Skeletal Formula:

Answer 5

Only shows the bonds of carbon atoms, with any functional groups. Hydrogen and Carbon ARE NOT shown. Good for large, complicated structures.

Question 6

Define Displayed Formula:

Answer 6

Shows how the atoms are arranged, and the bonds between them. e.g. H-C-C-C-C-H

Question 7

Define Homologous Series:

Answer 7

A set of Organic Compounds with the same functional group and general formula. Consecutive members differ by -CH₂-.

Question 8

Define Functional Group:

Answer 8

A group of atoms in a molecule responsible for the characteristic reactions of the compound.

Question 9

For an Alcohol list the: Formula, Prefix and Suffix.

Answer 9

Formula: -OH
Prefix: Hydroxyl-
Suffix: -ol

Question 10

For an Aldehyde list the: Formula, Prefix and Suffix.

Answer 10

Formula: -CHO (Double bond between C & O)
Prefix: None
Suffix: -al

Question 11

For an Alkane list the: Formula, Prefix and Suffix.

Answer 11

Formula: C-C
Prefix: None
Suffix: -ane

Question 12

For an Alkene list the: Formula, Prefix and Suffix.

Answer 12

Formula: C=C
Prefix: None
Suffix: -ene

Question 13

For a Carboxylic Acid list the: Formula, Prefix and Suffix.

Answer 13

Formula: -COOH (Two branches: -OH on one and =O on other)
Prefix: None
Suffix: -oic acid

Question 14

For a Haloalkane list the: Formula, Prefix and Suffix.

Answer 14

Formula: -F or -Br or -I etc.
Prefix: Fluro- or Chloro- etc
Suffix: None

Question 15

For a Keytone list the: Formula, Prefix and Suffix.

Answer 15

Formula: C-CO-C or C-C=O-C (C=O at right angle)
Prefix: None
Suffix: -one

Question 16

List the order of stem names:

Answer 16

1) Meth-, 2) Eth-, 3) Prop-, 4) But-, 5) Pent-, 6) Hex-, 7) Hept-, 8) Oct-, 9) Non-, 10) Dec-

Question 17

What do all Organic Compounds feature?

Answer 17

An Aromatic or Aliphatic carbon skeleton.

Question 18

What is the difference between Aliphatic and Aromatic compounds?

Answer 18

Aliphatic Compounds contain C & H joined together in branched or straight chains or non-aromatic rings.

Aromatic Compounds have a Benzene ring.

Question 19

Define Alicyclic:

Answer 19

Where a Aliphatic Compound contains a non-aromatic ring.

Question 20

What is the difference between Saturated and Unsaturated compounds?

Answer 20

• Saturated compounds only have single C-C bonds (like Alkanes).
• Unsaturated compounds have double or triple C=C bonds as well as Aromatic Groups.

Question 21

What is an Alkyl?

Answer 21

A fragment of a molecule with General Formula CnH2n+1. e.g methyl-

Question 22

Define Nomenclature:

Answer 22

The naming of Organic Compounds.

Question 23

Define the IUPAC System:

Answer 23

The standard way of giving any compound a systematic name.

Question 24

Describe the steps related to naming a molecule:

Answer 24

1) Count the carbons in the longest continuous carbon chain. This gives the stem.
2) The main functional group gives the prefix (or suffix if no prefix) as this shows the Homologous Series.
3) Number the Carbon chain so that the main functional group has the lowest possible number. If there are more than one longest chain, pick the one with the most side chains.
4) Put the number of the Carbon atom the most important functional group is on between the stem and suffix: e.g. pentan-2-ol.
5) Any side chains or less important functional groups are added as prefixes, in alphabetical order after the number of the carbon atom they are attached to.
6) If there are multiple identical side chains, use di-, tri- or tetra- before that part.