Unit 14 assignment 2
What are Structural isomers?
● Structural isomers are molecules with the same chemical formula but distinct bond
configurations. The varying positions of an atom, group of atoms, or bond give rise to
their diverse bond configurations.
What are the three types of structural isomers?
● Functional groups, chains, and positional isomers are the three categories of
structural isomerism.
Functional group isomers: Functional group isomerism is a kind of structural isomerism in
which isomers are structurally identical but have distinct functional groups due to the
positions of certain atoms.
Chain isomers: When a section of the hydrocarbon skeleton is positioned differently from
the rest of the carbon backbone, it is referred to as chain isomerism, a type of structural
isomerism.
, Positional isomers: Positional isomers are structures with the same functional group and
chemical formula but distinct functional group locations along the carbon backbone.
Type of isomer Boiling point Melting point State of matter Chemical properties
(°C) (°C)
Propanal 48.4 -81.5 Liquid Colourless and flammable
(C3H6O) with a pungent odour
Propanone 56.2 -94.7 Liquid Colourless and odourless
(C3H6O)
Pentane 36.1 -130.3 Liquid Colourless and a gasoline-like
(C5H12) odour
Isopentane 27.8 -160.0 Gas Colourless and alcohol-like
(C5H12) odour
1-butene -6.3 -185.3 Gas Colourless and highly
(C4H8) flammable
2-butene -6.9 -185.2 Gas Colourless
(C4H8)
What are stereoisomers?
● A stereoisomer is a pair of molecules that differ from one another in terms of their
three-dimensional structure, but have the same chemical formula and atom
connections.
What are Structural isomers?
● Structural isomers are molecules with the same chemical formula but distinct bond
configurations. The varying positions of an atom, group of atoms, or bond give rise to
their diverse bond configurations.
What are the three types of structural isomers?
● Functional groups, chains, and positional isomers are the three categories of
structural isomerism.
Functional group isomers: Functional group isomerism is a kind of structural isomerism in
which isomers are structurally identical but have distinct functional groups due to the
positions of certain atoms.
Chain isomers: When a section of the hydrocarbon skeleton is positioned differently from
the rest of the carbon backbone, it is referred to as chain isomerism, a type of structural
isomerism.
, Positional isomers: Positional isomers are structures with the same functional group and
chemical formula but distinct functional group locations along the carbon backbone.
Type of isomer Boiling point Melting point State of matter Chemical properties
(°C) (°C)
Propanal 48.4 -81.5 Liquid Colourless and flammable
(C3H6O) with a pungent odour
Propanone 56.2 -94.7 Liquid Colourless and odourless
(C3H6O)
Pentane 36.1 -130.3 Liquid Colourless and a gasoline-like
(C5H12) odour
Isopentane 27.8 -160.0 Gas Colourless and alcohol-like
(C5H12) odour
1-butene -6.3 -185.3 Gas Colourless and highly
(C4H8) flammable
2-butene -6.9 -185.2 Gas Colourless
(C4H8)
What are stereoisomers?
● A stereoisomer is a pair of molecules that differ from one another in terms of their
three-dimensional structure, but have the same chemical formula and atom
connections.
