Paper 2 - AQA GCSE Chemistry
"Definition of a carbon footprint - CORRECT ANSWER The total greenhouse gases
emitted over the full life cycle of a product, service or event."
"Condensation polymerisation - CORRECT ANSWER Condensation polymerisation
involves monomers with two functional groups. When these types of monomers react
they join together, usually losing small molecules such as water, and so the reactions
are called condensation reactions."
"Dicarboxylic acid reacting with a diol (example of a condensation polymer) - CORRECT
ANSWER lol
The resultant polymer is a polyester."
"Amino acids - CORRECT ANSWER An amino acid contains two different functional
groups: a basic amino group (NH₂) and a carboxyl group (COOH), e.g. glycine, the
smallest amino acid.
Amino acids can form polypeptides via condensation polymerisation. The amino acid
group can react with the acid group of another (continuously) forming a polymer chain.
For every new bond formed another water molecule is lost."
"Proteins - CORRECT ANSWER Proteins are multiple long chain polypeptides. They
have many uses:
- Form enzymes which work as catalysts speeding up reactions in the human body
- Form Haemoglobin which in red blood cells transport oxygen around the body
- Form antibodies which are important for our immune system. They find at get rid of
bacteria and viruses
- Form the majority of body tissue"
"DNA - CORRECT ANSWER DNA is a large molecule essential for life that encodes
genetic instructions for the development and functioning of living organisms and viruses.
Most DNA molecules are two polymer chains, made from 4 different molecules called a
nucleotides, in a double helix structure. The monomers that make up DNA are
nucleotides."
"Other naturally occurring polymers - CORRECT ANSWER Other important polymers
for life are starch made from glucose monomers, cellulose made from glucose
monomers and proteins made from amino acid monomers."
"Number of types of monomers in addition polymerisation - CORRECT ANSWER Only
one monomer type containing a C=C bond."
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, "Number of types of monomers in condensation polymerisation - CORRECT ANSWER
Either two monomer types with the same functional groups, or one monomer type with
two different functional groups."
"Number of products in addition polymerisation - CORRECT ANSWER One."
"Number of products in condensation polymerisation - CORRECT ANSWER Two, the
polymer and a small molecule."
"Function groups involved in addition polymerisation - CORRECT ANSWER A C=C
bond."
"Function groups involved in condensation polymerisation - CORRECT ANSWER Two
reactive groups on each monomer."
"Pure substance - CORRECT ANSWER A pure substance is a single element or
compound, which is not mixed with anything. These melt and boil at specific
temperatures, and if they don't you know they are impure."
"Formulation - CORRECT ANSWER This is a mixture that has been designed for a
useful purpose. These are made by mixing the components of the mixture in specific
amounts, when each chemical in it has a particular purpose. These measured quantities
allow the formulation to have required properties. Examples include:
- Fuels
- Cleaning agnets
- Paints
- Medicines
- Alloys
- Fertilisers
- Foods"
"Definition of a pure substance - CORRECT ANSWER A substance made up of a
single element or compound that is not mixed with anything."
"How to determine if a substance is pure - CORRECT ANSWER It will melt and boil at
a specific temperature."
"Properties of an impure substance in comparison with a pure substance - CORRECT
ANSWER - An impurity will lower the the melting point and increase the melting range
of a pure substance.
- It also increases the boiling point and may result in a substance boiling over a wider
range of temperatures."
"Why an impurity lowers boiling point using the example of a solution with a dissolved
salt as an impurity - CORRECT ANSWER In order to dissolve the impurity the solvent
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must disrupt some of its interactions with other solvent molecules. When something is
, frozen its molecules are interacting strongly with eachother, throwing in impurities
breaks those interactions and keeps the solvent liquid."
"Definition of a formulation - CORRECT ANSWER A formulation is a mixture that has
been designed as a useful product."
"Hydrocarbon - CORRECT ANSWER A hydrocarbon is a material that contains only
carbon and hydrogen atoms."
"Alkanes - CORRECT ANSWER - These are saturated, meaning there are only single
bonds between atoms
- They are relatively unreactive, although they do combust
- Their single bonds are quite strong
- They are a homologous series of hydrocarbons (organic compounds with the same
functional group and similar chemical properties)
- There are trends in their physical properties"
"Formula for alkanes - CORRECT ANSWER Cn H2n+2"
"The first four alkanes - CORRECT ANSWER - Methane
- Ethane
- Propane
- Butane"
"Formula for methane - CORRECT ANSWER CH₄"
"Formula for ethane - CORRECT ANSWER C₂H₆"
"Formula for propane - CORRECT ANSWER C₃H₈"
"Formula for butane - CORRECT ANSWER C₄H₁₀"
"Crude oil - CORRECT ANSWER - A finite resource found in rocks
- Mostly ancient biomass, e.g. plankton, which has been buried in mud
- It is a mixture of many compounds, mostly hydrocarbons, which are mostly alkanes
- They are separated by fractional distillation"
"Why fractional distillation works - CORRECT ANSWER The hydrocarbons in crude oil
can be separated into fractions, which are chemicals that have a similar boiling point.
These are molecules with a similar number of carbon atoms. Each fraction has different
properties and uses, a lot of which are processed to produce fuels and feedstock for the
petrochemical industry, e.g. petrol, kerosene, heavy fuel oil and liquefied petroleum
gases."
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Page
"Definition of a carbon footprint - CORRECT ANSWER The total greenhouse gases
emitted over the full life cycle of a product, service or event."
"Condensation polymerisation - CORRECT ANSWER Condensation polymerisation
involves monomers with two functional groups. When these types of monomers react
they join together, usually losing small molecules such as water, and so the reactions
are called condensation reactions."
"Dicarboxylic acid reacting with a diol (example of a condensation polymer) - CORRECT
ANSWER lol
The resultant polymer is a polyester."
"Amino acids - CORRECT ANSWER An amino acid contains two different functional
groups: a basic amino group (NH₂) and a carboxyl group (COOH), e.g. glycine, the
smallest amino acid.
Amino acids can form polypeptides via condensation polymerisation. The amino acid
group can react with the acid group of another (continuously) forming a polymer chain.
For every new bond formed another water molecule is lost."
"Proteins - CORRECT ANSWER Proteins are multiple long chain polypeptides. They
have many uses:
- Form enzymes which work as catalysts speeding up reactions in the human body
- Form Haemoglobin which in red blood cells transport oxygen around the body
- Form antibodies which are important for our immune system. They find at get rid of
bacteria and viruses
- Form the majority of body tissue"
"DNA - CORRECT ANSWER DNA is a large molecule essential for life that encodes
genetic instructions for the development and functioning of living organisms and viruses.
Most DNA molecules are two polymer chains, made from 4 different molecules called a
nucleotides, in a double helix structure. The monomers that make up DNA are
nucleotides."
"Other naturally occurring polymers - CORRECT ANSWER Other important polymers
for life are starch made from glucose monomers, cellulose made from glucose
monomers and proteins made from amino acid monomers."
"Number of types of monomers in addition polymerisation - CORRECT ANSWER Only
one monomer type containing a C=C bond."
1
Page
, "Number of types of monomers in condensation polymerisation - CORRECT ANSWER
Either two monomer types with the same functional groups, or one monomer type with
two different functional groups."
"Number of products in addition polymerisation - CORRECT ANSWER One."
"Number of products in condensation polymerisation - CORRECT ANSWER Two, the
polymer and a small molecule."
"Function groups involved in addition polymerisation - CORRECT ANSWER A C=C
bond."
"Function groups involved in condensation polymerisation - CORRECT ANSWER Two
reactive groups on each monomer."
"Pure substance - CORRECT ANSWER A pure substance is a single element or
compound, which is not mixed with anything. These melt and boil at specific
temperatures, and if they don't you know they are impure."
"Formulation - CORRECT ANSWER This is a mixture that has been designed for a
useful purpose. These are made by mixing the components of the mixture in specific
amounts, when each chemical in it has a particular purpose. These measured quantities
allow the formulation to have required properties. Examples include:
- Fuels
- Cleaning agnets
- Paints
- Medicines
- Alloys
- Fertilisers
- Foods"
"Definition of a pure substance - CORRECT ANSWER A substance made up of a
single element or compound that is not mixed with anything."
"How to determine if a substance is pure - CORRECT ANSWER It will melt and boil at
a specific temperature."
"Properties of an impure substance in comparison with a pure substance - CORRECT
ANSWER - An impurity will lower the the melting point and increase the melting range
of a pure substance.
- It also increases the boiling point and may result in a substance boiling over a wider
range of temperatures."
"Why an impurity lowers boiling point using the example of a solution with a dissolved
salt as an impurity - CORRECT ANSWER In order to dissolve the impurity the solvent
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Page
must disrupt some of its interactions with other solvent molecules. When something is
, frozen its molecules are interacting strongly with eachother, throwing in impurities
breaks those interactions and keeps the solvent liquid."
"Definition of a formulation - CORRECT ANSWER A formulation is a mixture that has
been designed as a useful product."
"Hydrocarbon - CORRECT ANSWER A hydrocarbon is a material that contains only
carbon and hydrogen atoms."
"Alkanes - CORRECT ANSWER - These are saturated, meaning there are only single
bonds between atoms
- They are relatively unreactive, although they do combust
- Their single bonds are quite strong
- They are a homologous series of hydrocarbons (organic compounds with the same
functional group and similar chemical properties)
- There are trends in their physical properties"
"Formula for alkanes - CORRECT ANSWER Cn H2n+2"
"The first four alkanes - CORRECT ANSWER - Methane
- Ethane
- Propane
- Butane"
"Formula for methane - CORRECT ANSWER CH₄"
"Formula for ethane - CORRECT ANSWER C₂H₆"
"Formula for propane - CORRECT ANSWER C₃H₈"
"Formula for butane - CORRECT ANSWER C₄H₁₀"
"Crude oil - CORRECT ANSWER - A finite resource found in rocks
- Mostly ancient biomass, e.g. plankton, which has been buried in mud
- It is a mixture of many compounds, mostly hydrocarbons, which are mostly alkanes
- They are separated by fractional distillation"
"Why fractional distillation works - CORRECT ANSWER The hydrocarbons in crude oil
can be separated into fractions, which are chemicals that have a similar boiling point.
These are molecules with a similar number of carbon atoms. Each fraction has different
properties and uses, a lot of which are processed to produce fuels and feedstock for the
petrochemical industry, e.g. petrol, kerosene, heavy fuel oil and liquefied petroleum
gases."
3
Page
