Nomenclature and Isomers

Question 1

How many bonds does Carbon form?

Answer 1

4

Question 2

Displayed formula

Answer 2

Shows every atom and every bond in the molecule

Question 3

Structural formula

Answer 3

Shows the unique arrangement of atoms in a molecule without showing all the bonds e.g CH3CH3

Question 4

Skeletal formula

Answer 4

Simplified displayed formula where each vertex represents a carbon atom and each line is a C-C bond and each carbon is assumed to have enough C-H bonds to make a total of 4 bonds.
e.g - is ethane

Question 5

How to name an organic compound

Answer 5

Look for the longest chain of C atoms and name it. Identify any side chains and add the name to the front. Find the number carbon atom of the chain it is attached to and add this before the side chain name (count from which ever end gives you the lowest number). If there are more than one of the same side chain add all the carbon atom number to the front and add a suitable prefix to the side chain name e.g di-

Question 6

Functional group

Answer 6

An atom or group of atoms in an organic molecule which is responsible for the characteristic reactions of that molecule.

Question 7

General formula of ketones

Answer 7

RCOR

Question 8

General formula of aldehydes

Answer 8

RCOH

Question 9

Define isomers

Answer 9

Molecules with the same molecular formula but with different arrangements of the atoms.

Question 10

Chain isomers

Answer 10

Where the hydrocarbon chain has the same functional group but is arranged differently.
e.g butane and 2-methyl propane

Question 11

Positional isomers

Answer 11

The same functional groups or side chains are attached to different positions on the same main chain.

Question 12

Functional group isomers

Answer 12

The functional groups are different but there is the same molecular formula
e.g aldehydes and ketones

Question 13

Stereoisomers

Answer 13

Where two or more compounds have the same structural formula but they differ in the arrangement of the bonds in space.

Question 14

How to work out E-Z isomerism

Answer 14

Identify the heaviest element bonded to each carbon either side of a C=C. If they are on opposite sides the add (E)- to the start of the name. If they are on the same side add (Z)- to the start of the name. (Only works with double bonds because the carbons either side can’t rotate).

Question 15

How are amines formed?

Answer 15

The hydrogen atoms in ammonia have been replaced by aryl or alkyl groups.
It is a primary amine when only one H is replaced, (etc. up to 3 Hs)

Question 16

Nitrile functional group

Answer 16

CN (3 double bonds)

Question 17

Define homologous series

Answer 17

A family of organic compounds with the same functional group but different carbon chain lengths.