Edexcel A level Chemistry Paper 2 Exam
Questions and Answers 2024 Review
Nucleophile - Answer>>A species that donates a lone pair of
electrons. Examples include ammonia, water and cyanide.
Electrophile - Answer>>A species that accepts a pair of
electrons. The most common example is H+ that accepts a lone
pair of electrons from a nitrogen atom in ammonia.
Nucleophilic substitution - Answer>>A substitution reaction in
which a nucleophile such as ammonia is attracted to a positive
charge centre such as the functional group carbon atom of a
halogenoalkane.
Hydrolysis - Answer>>Breaking up a molecule using water.
There are two types of hydrolysis - acidic and alkaline
Ester - Answer>>A molecule that contains the COO functional
group. Many esters are volatile and are found in fragrances such
as rose oil.
Ester solubility in water - Answer>>The middle of the molecule
has has hydrogen bonding between the oxygen of C=O and the H
of water; and also between the -O- and the H of water. The
smaller the molecule the higher the solubility in water.
Ester solubility in hexane (non-polar solvent) - Answer>>The
non-polar alkyl ends of the molecule form London forces with the
solvent. The larger the molecule, the greater the solubility in the
hexane solvent because there are more London forces between
the solute molecule and the solvent molecule.
Ammonia - Answer>>NH3
, Primary amine - Answer>>CH3NH2
Secondary amine - Answer>>(CH3)2NH
Tertiary amine - Answer>>(CH3)3N
Free radical substitution - Answer>>When a halogen atom
replaces a hydrogen atom in a reaction. UV is required. At higher
levels of the halogen, the amount of substitution increases. For
example, CCL4 is formed at high CL2 levels, CH3Cl is formed at
low Cl2 levels. 3 steps I,P,T.
Electrophilic addition - Answer>>A type of addition reaction in
which an electrophile is attracted to an electron-rich centre or
atom, where it accepts a pair of electrons to form a new covalent
bond.
Example - symbol equation - free radical substitution at low UV
levels - Answer>>Cl2 + CH4 --> CH3Cl + HCl
Example - symbol equation - free radical substitution at high UV
levels - Answer>>4Cl2 + CH4 --> CCl4 + 4HCl
Example - symbol equation - electrophilic addition -
Answer>>C2H4 + Cl2 --> C2H4Cl2
Example - symbol equation - addition polymerisation -
Answer>>n C2H4 --> [C2H4]n
Structural isomerism - Answer>>Atoms are joined in a different
order forming different structures
Questions and Answers 2024 Review
Nucleophile - Answer>>A species that donates a lone pair of
electrons. Examples include ammonia, water and cyanide.
Electrophile - Answer>>A species that accepts a pair of
electrons. The most common example is H+ that accepts a lone
pair of electrons from a nitrogen atom in ammonia.
Nucleophilic substitution - Answer>>A substitution reaction in
which a nucleophile such as ammonia is attracted to a positive
charge centre such as the functional group carbon atom of a
halogenoalkane.
Hydrolysis - Answer>>Breaking up a molecule using water.
There are two types of hydrolysis - acidic and alkaline
Ester - Answer>>A molecule that contains the COO functional
group. Many esters are volatile and are found in fragrances such
as rose oil.
Ester solubility in water - Answer>>The middle of the molecule
has has hydrogen bonding between the oxygen of C=O and the H
of water; and also between the -O- and the H of water. The
smaller the molecule the higher the solubility in water.
Ester solubility in hexane (non-polar solvent) - Answer>>The
non-polar alkyl ends of the molecule form London forces with the
solvent. The larger the molecule, the greater the solubility in the
hexane solvent because there are more London forces between
the solute molecule and the solvent molecule.
Ammonia - Answer>>NH3
, Primary amine - Answer>>CH3NH2
Secondary amine - Answer>>(CH3)2NH
Tertiary amine - Answer>>(CH3)3N
Free radical substitution - Answer>>When a halogen atom
replaces a hydrogen atom in a reaction. UV is required. At higher
levels of the halogen, the amount of substitution increases. For
example, CCL4 is formed at high CL2 levels, CH3Cl is formed at
low Cl2 levels. 3 steps I,P,T.
Electrophilic addition - Answer>>A type of addition reaction in
which an electrophile is attracted to an electron-rich centre or
atom, where it accepts a pair of electrons to form a new covalent
bond.
Example - symbol equation - free radical substitution at low UV
levels - Answer>>Cl2 + CH4 --> CH3Cl + HCl
Example - symbol equation - free radical substitution at high UV
levels - Answer>>4Cl2 + CH4 --> CCl4 + 4HCl
Example - symbol equation - electrophilic addition -
Answer>>C2H4 + Cl2 --> C2H4Cl2
Example - symbol equation - addition polymerisation -
Answer>>n C2H4 --> [C2H4]n
Structural isomerism - Answer>>Atoms are joined in a different
order forming different structures
