Applied Science Unit 14, Assignment FULL ASSIGNMENT (NEW SPEC) Isomer assignment.

ISOMERS




UNIT 14

, Isomers



Isomers
An Isomer of a molecule is a compound with the same molecular formula but a different structural formular or
different arrangement of atoms. There are two different types of an isomer structural isomers and
stereoisomers.

STRUCTURAL ISOMERS: are compounds with the same molecular formular but different structural formular.
There are three types of structure isomers chain isomers, positional isomers, and functional isomers.

 Chain isomers this is where the isomers differ in the order in which the carbon atoms are bonded to
each other.
Example 1: PENTANE WHICH HAS THREE ISOMERS 2- METHYL BUTANE AND 2,2-
dimethylpropane.




Structure formula:
3D model of pentane
3D models of 2- methyl butane

3D models of 2,2-
dimethylpropane




Physical and chemical properties
Pentane Colour- colourless
Melting point- (-130.5°C to -129°C (-203°F to 264°F)
Boling point- (35.9°C to 36.3°C (96.6°F to 97.3°F)
Density- 0.626 g/cm3 (at 20°C)
Solubility- 0.04 g/L (liquid at 20 °C)
2-methyl butane Colour - colourless
Melting point- (-160 °C)
Boling point- (30°C)
Density- 0.62 g/cm3 at 25 °C
Solubility- 0.0485 g/l at 25°C
2,2-dimethylpropane Colour - COLOURLESS COMPRESSED GAS WITH CHARACTERISTIC
ODOUR.
Melting point- (-16.6°C)
Boling point- (9.5°C)
Density- 0.61 g/cm³ at 20 °C
Solubility- none