3 a) intro

Question 1

3.1-Homologous series:

It is a family of compounds with same functional group and general formula with similar physical and chemical properties.

Characteristics of homologous series:

They have a general formula
They differs in molecular formula
A homologous series have similar properties
They have a trend
Each homologous series have a functional of group

Answer 1

Homologous series:
It is a family of compounds with same functional group and general formula with similar physical and chemical properties.

Characteristics of homologous series:

• They have a general formula
• They differs in molecular formula
• A homologous series have similar properties
• They have a trend
• Each homologous series have a functional of group
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Hydrocarbon:

Compounds that are made of only hydrogen and carbon. Hydrocarbons are of two types: Saturated and Unsaturated

Saturated

Unsaturated

Contain C-C single bond(eg: Alkanes)

Contain C=C double bond. (eg: alkenes)

Give substitution reaction

Give addition reaction

A part of saturated compound comparatively is less

A part of unsaturated is more reactive than saturated

reactive

Alkanes do not polimarise

Alkene can be polimarised

Saturated hydrocarbons cannot change the colour of

Unsaturated hydrocarbons can change the colour of

bromine water

bromine water

General formula:

General formula confirms which compound is in which homologous series.

Alkanes==>CnH

Alkenes ==> CH2n

Alcohols==>CnH2n+1+ OH

Isomerism:

Molecules with identical molecular formulae but with different structural formulae. Examples:

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