Nomenclature and isomerism in organic compounds

Question 1

What are the five main types of formulae for organic compounds?

Answer 1

1) Molecular formula - The actual numbers of atoms of each element in a molecule
2) Structural formula - Structure is shown
3) Condensed structural formula - CH3CH2OH etc
4) Empirical formula - The simplest whole number ratio of the atoms of different elements in a compound
5) Skeletal - Carbon backbone in a zigzag arrangement.

Question 2

Give the order of priority, from highest to lowest, of the functional groups.

Answer 2

Carboxylic acid –> Nitrile –> Aldehyde –> Ketone –> Alcohol –> Amine –> Alkene – Alkane –> Halogenoalkane.

Question 3

What is structural isomerism?

Answer 3

Compounds that have the same molecular formula but a different structural formula.

Question 4

What are the three ways in which structural isomerism can occur?

Answer 4

1) Chain isomerism - Same molecular formula but a different arrangement of atoms in the carbon chain
2) Positional isomerism - Same functional group but its in a different position
3) Functional group isomerism - Same molecular formula but different functional groups.

Question 5

What are the two functional group isomers I will come across?

Answer 5

Esters are functional groups isomers of Carboxylic acids

Aldehydes are function group isomers of Ketones

Question 6

What are geometric isomers?

Answer 6

Molecules that have the same structural formula bur different arrangement of atoms due to the presence of one or more C=C bonds.

Question 7

What does the C=C bond act as?

Answer 7

The C=C bond acts as an energy barrier to free rotation. The cause of geometric (E/Z) isomerism in alkenes.

Question 8

What does C-C allow?

Answer 8

Free rotation