5/2/26, 6:29 QCAA Chemistry: Units 3 + 4
AM
QCAA Chemistry Units 3 & 4 (Year 12) – 350+ Exam Questions
with Verified Answers, Organic & Inorganic Chemistry Notes,
Reaction Mechanisms, Polymers, Biochemistry & Full Exam
Revision Guide.
Organic/Carbon Chemistry Study of carbon containing compounds.
Inorganic Chemistry The study of chemicals that do not contain carbon.
Hydrocarbons Organic molecules that are composed of only
carbon and hydrogen and are the main constitutes
of natural gas and crude oil.
Cyclic Hydrocarbons Hydrocarbon compounds with closed rings of
carbon atoms. Can be classed as alicyclic
compounds or aromatic compounds.
Aliphatic Hydrocarbons Hydrocarbon compounds which do not contain
rings.
Saturated Hydrocarbons A hydrocarbon in which all the C-C and C-H bonds
are single bonds.
Unsaturated Hydrocarbons A hydrocarbon in which one or more of the bonds
between carbon atoms is double or triple bond.
Alkane A hydrocarbon containing only single covalent bonds
and whose homologous series general formula is
CnH(2n+2).
Homologous Series A series of organic compounds with the same
functional group but with each successive member
differing by CH2.
Molecular Formula A chemical formula that shows the number and
kinds of atoms in a molecule, but not the
arrangement of the atoms.
Structural Formula A formula that shows the arrangement of atoms in
the molecule of a compound.
Condensed Formula A formula which shows all of the atoms in a
molecule and places them in a sequential
arrangement that details which atoms are bonded
to each other.
Skeletal/Line Formula A formula which shows carbon skeleton when all H is
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removed, assume there is carbon at an location
where lines meet and that there is a carbon at the
end of each line, and correct H bonding.
Alkenes Hydrocarbons with one or more carbon-carbon
double bonds.
Alkynes Hydrocarbons with one or more triple bonds
between carbon atoms.
Substituted Hydrocarbons A hydrocarbon in which one or more hydrogen
atoms have been replaced by atoms of other
elements.
Functional Group Atom or group of atoms in a molecule principally
responsible for the chemical and physical properties
of that molecule.
Substituent An atom or group of atoms that can take the place
of a hydrogen atom on a parent hydrocarbon
molecule.
Parent Compound The longest carbon chain in a hydrocarbon.
Locant In nomenclature, a number used to identify the
location of a substituent.
Isomers/Isomerism Compounds with the same chemical formula that
differ in the arrangement of their atoms.
Structural Isomers Organic compounds which have the same molecular
formula but different structural formulae (eg. atoms
ares linked in different ways and sequences) and so
have very different chemical and physical
properties. eg. chain and positional isomers.
Chain Isomers Structural isomers that differ in the arrangement of
their carbon chains, may be straight or branched.
Positional Isomers Structural isomers which differ in the positions of a
functional group but possess the same carbon
skeleton.
Stereoisomers Organic compounds with the same molecular
formula and structural formula but having different
arrangements of atoms in spacial or three-
dimensional arrangement. eg. geometric and
optical isomers.
Geometrical Isomerism Stereoisomers which have the same structural
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formula (so also same molecular formula), but a
different spatial arrangement of atoms around a
double bond or ring.
Optical Isomerism Stereoisomers in which the isomers cause plane
polarized light to rotate in different directions.
Trans-isomer An isomer of an alkene in which similar groups are
on opposite sides of the double bond.
Cis-isomer An isomer of an alkene in which similar groups are
on the same side of the double bond.
Alicyclic Compounds Are aliphatic compounds arranged in non-aromatic
rings joined by single bonds.
Aromatic Compounds Organic compounds that contain at least one
benzene ring.
Benzene Organic chemical compound with the molecular
formula C6H6.
Cycloalkanes Saturated hydrocarbons with carbon atoms joined
in a ring.
Haloalkanes Alkanes with a halogen substituent.
Primary Haloalkanes The carbon which carries the halogen atom is only
attached to one other alkyl group.
Secondary Haloalkanes The carbon with the halogen attached is joined
directly to two other alkyl groups, which may be the
same or different.
Tertiary Haloalkanes The carbon atom holding the halogen is attached
directly to three alkyl groups, which may be any
combination of the same or different.
Alcohols Organic compounds containing hydroxyl groups.
Primary Alcohols An alcohol in which the OH group is attached to a
carbon atom that is attached to two or three
hydrogen atoms.
Secondary Alcohols Two carbons attached to the carbon with the
hydroxyl functional group.
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AM
QCAA Chemistry Units 3 & 4 (Year 12) – 350+ Exam Questions
with Verified Answers, Organic & Inorganic Chemistry Notes,
Reaction Mechanisms, Polymers, Biochemistry & Full Exam
Revision Guide.
Organic/Carbon Chemistry Study of carbon containing compounds.
Inorganic Chemistry The study of chemicals that do not contain carbon.
Hydrocarbons Organic molecules that are composed of only
carbon and hydrogen and are the main constitutes
of natural gas and crude oil.
Cyclic Hydrocarbons Hydrocarbon compounds with closed rings of
carbon atoms. Can be classed as alicyclic
compounds or aromatic compounds.
Aliphatic Hydrocarbons Hydrocarbon compounds which do not contain
rings.
Saturated Hydrocarbons A hydrocarbon in which all the C-C and C-H bonds
are single bonds.
Unsaturated Hydrocarbons A hydrocarbon in which one or more of the bonds
between carbon atoms is double or triple bond.
Alkane A hydrocarbon containing only single covalent bonds
and whose homologous series general formula is
CnH(2n+2).
Homologous Series A series of organic compounds with the same
functional group but with each successive member
differing by CH2.
Molecular Formula A chemical formula that shows the number and
kinds of atoms in a molecule, but not the
arrangement of the atoms.
Structural Formula A formula that shows the arrangement of atoms in
the molecule of a compound.
Condensed Formula A formula which shows all of the atoms in a
molecule and places them in a sequential
arrangement that details which atoms are bonded
to each other.
Skeletal/Line Formula A formula which shows carbon skeleton when all H is
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removed, assume there is carbon at an location
where lines meet and that there is a carbon at the
end of each line, and correct H bonding.
Alkenes Hydrocarbons with one or more carbon-carbon
double bonds.
Alkynes Hydrocarbons with one or more triple bonds
between carbon atoms.
Substituted Hydrocarbons A hydrocarbon in which one or more hydrogen
atoms have been replaced by atoms of other
elements.
Functional Group Atom or group of atoms in a molecule principally
responsible for the chemical and physical properties
of that molecule.
Substituent An atom or group of atoms that can take the place
of a hydrogen atom on a parent hydrocarbon
molecule.
Parent Compound The longest carbon chain in a hydrocarbon.
Locant In nomenclature, a number used to identify the
location of a substituent.
Isomers/Isomerism Compounds with the same chemical formula that
differ in the arrangement of their atoms.
Structural Isomers Organic compounds which have the same molecular
formula but different structural formulae (eg. atoms
ares linked in different ways and sequences) and so
have very different chemical and physical
properties. eg. chain and positional isomers.
Chain Isomers Structural isomers that differ in the arrangement of
their carbon chains, may be straight or branched.
Positional Isomers Structural isomers which differ in the positions of a
functional group but possess the same carbon
skeleton.
Stereoisomers Organic compounds with the same molecular
formula and structural formula but having different
arrangements of atoms in spacial or three-
dimensional arrangement. eg. geometric and
optical isomers.
Geometrical Isomerism Stereoisomers which have the same structural
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formula (so also same molecular formula), but a
different spatial arrangement of atoms around a
double bond or ring.
Optical Isomerism Stereoisomers in which the isomers cause plane
polarized light to rotate in different directions.
Trans-isomer An isomer of an alkene in which similar groups are
on opposite sides of the double bond.
Cis-isomer An isomer of an alkene in which similar groups are
on the same side of the double bond.
Alicyclic Compounds Are aliphatic compounds arranged in non-aromatic
rings joined by single bonds.
Aromatic Compounds Organic compounds that contain at least one
benzene ring.
Benzene Organic chemical compound with the molecular
formula C6H6.
Cycloalkanes Saturated hydrocarbons with carbon atoms joined
in a ring.
Haloalkanes Alkanes with a halogen substituent.
Primary Haloalkanes The carbon which carries the halogen atom is only
attached to one other alkyl group.
Secondary Haloalkanes The carbon with the halogen attached is joined
directly to two other alkyl groups, which may be the
same or different.
Tertiary Haloalkanes The carbon atom holding the halogen is attached
directly to three alkyl groups, which may be any
combination of the same or different.
Alcohols Organic compounds containing hydroxyl groups.
Primary Alcohols An alcohol in which the OH group is attached to a
carbon atom that is attached to two or three
hydrogen atoms.
Secondary Alcohols Two carbons attached to the carbon with the
hydroxyl functional group.
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