3.1 Introduction to Organic Chemistry

Question 1

Empirical formula

Answer 1

Simplest whole number ratio of atoms in a molecule

Question 2

Molecular formula

Answer 2

Gives the actual number of atoms of different elements in a molecule

Question 3

Define displayed formula

Answer 3

Shows every atom and every bond in a molecule

Question 4

Define structural formula

Answer 4

Shows arrangement of atoms in a molecule without showing every bond

Question 5

Define skeletal formula

Answer 5

Drawn as lines with each vertex being a carbon atom. Carbon atoms not drawn, assumed each C atom has all unspecified bonds as C-H

Question 6

Define structural isomerism

Answer 6

When molecules have the same molecular formula but different structural formula

Question 7

What is positional isomerism?

Answer 7

Functional group is attached to the main chain at a different place

Question 8

What is functional group isomerism?

Answer 8

Same atoms but a different functional group due to a different arrangement of atoms

Question 9

What is chain isomerism?

Answer 9

Hydrocarbon chain organised differently e.g. branched chains

Question 10

Define stereoisomerism.

Answer 10

When molecules have the same structural and molecular formula, but have a different arrangement of atoms in space

Question 11

What is E-Z isomerism and how are the E and Z isomers decided?

Answer 11

E-Z isomerism is caused by the limited rotation about C=C double bonds
If the two substituents with the highest molecular mass are on the same side of the double bond, it is the Z (zusammen) isomer
If they are on different sides, it is the E (entgegen) isomer