Page 33 - Ranger SPM 2022 Chemistry

Chemistry SPM Chapter 2 Carbon Compound
2. Isomers are compounds with the
Isomers and same molecular formula but different
2.4 Naming based structural formulae.
on IUPAC 3. Isomers show:
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Nomenclature (a) Same chemical properties
because they have the same
functional group.
(b) Different physical properties
1. Structural isomerism is a phenomenon because the more branches they
where a compound has the same have, the lower their melting
molecular formula but with different point and boiling point.
structural formulae.

Structural Isomerism

Chain isomerism Position isomerism
• Arrangements of carbon chains are • Positions of functional group are different
different (straight chain / branched chain) on the same carbon chain

H H H H H Chain H H H H H H H H
H C C C C H H C H H C C C C H H C C C C H
H H
H H H H H H H H
H C C C H
Double bond on
Straight chain Double bond on the second carbon
the first carbon
H H H
Branched chain

4. Steps in drawing isomers:

Form 5
Alkane • Draw an atomic structure in a straight chain.
• Draw a branched chain.

Alkene • Draw an atomic structure in a straight chain.
• Change the position of the double bond (=) or triple bond (≡).
Alkyne • Draw a branched chain in every straight chain with different
positions of double bond (=) or triple bond (≡).

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02.5 RANGER SPM CHEMISTRY 2P.indd 162 29/03/2022 2:28 PM