AQA A-level Chemistry paper 2 with correct
answers
Relative atomic mass (Ar) - correct answers-Average mass of an atom compared with
one twelth of the mass of an atom of carbon 12
Electronegativity - correct answers-Power of an atom to attract the pair of electrons in a
covalent bond
Standard enthalpy of combustion - correct answers-Enthalpy change when 1 mole of a
substance burns completely in oxygen under standard conditions with all reactants and
products being in their standard state
Standard enthalpy of formation - correct answers-Enthalpy change when 1 mole of a
compound is formed from it's elements under standard conditions in their standard
states
Mean bond enthalpy - correct answers-The average energy needed to break a certain
type of bond over a range of compounds
Activation energy - correct answers-Minimum energy required for colliding molecules to
react
Maxwell-Boltzmann distribution x and y axes - correct answers-x: Energy
y: fraction/number of molecules
What happens to the Maxwell-Boltzmann curve when temperature increases - correct
answers-Moves down and to the right
Rate of reaction - correct answers-Rate at which product formed/reactant used up
Order of reaction - correct answers-Power to which the concentration of a species is
raised in the rate equation
rearrange k=Ae^-Ea/Rt - correct answers-lnk=-Ea/Rt+lnA
Conditions for thermal cracking - correct answers-High temperature and high pressure
Products of thermal cracking - correct answers-High % of alkenes
Conditions for catalytic cracking - correct answers-High temperature ,slight pressure
and in the presence of a zeolite catalyst
Products of catalytic cracking - correct answers-Motor fuels and aromatic hydrocarbons
, Why do we crack alkanes? - correct answers-Smaller alkanes/alkenes generally more
useful than longer chain ones
Equation for complete combustion of alkanes - correct answers-alkane + oxygen >
carbon dioxide + water
Equations for incomplete combustion of alkanes - correct answers-alkane + oxygen >
carbon monoxide/carbon + water
Pollutants produced by combustion engines - correct answers-NOx, CO, C and
sunburned hydrocarbons
Reaction of methane with chlorine - correct answers-I: Cl2 > 2Cl•
P: CH4 + Cl• > CH3• + Chi
CH3• + Cl2 > CH3Cl + Cl•
T: CH3• + Cl• > CH3Cl
2 equations showing decomposition of the ozone - correct answers-Cl• + O3 > ClO• +
O2
ClO• + O3 > 2O2 + Cl•
What types of mechanism do haloalkanes undergo? - correct answers--Nucleophilic
substitution by aqueous hydroxide ions, cyanide ions or ammonia
-Elimination with ethanolic hydroxide ions
What type of mechanism do alkenes undergo? - correct answers-Electrophilic addition
by bromine, hydrogen bromide or sulphuric acid
Test for primary or secondary alcohols - correct answers-Warm with acidified potassium
dichromate (VI) and positive result is Solution turning green
Tests for aldehyde or ketone - correct answers--Warm with Fehlings Solution - brick red
precipitate indicates aldehyde
-Warm with Tollens reagent (silver nitrate + sodium hydroxide + dilute ammonia) -
aldehyde gives a silver mirror
Test for alkenes - correct answers-Shake with bromine water- alkene goes from Orange
to colourless
Test for carboxylic acids - correct answers-Sodium carbonate and effervescence is
positive
Relative stabilities of carbocations - correct answers-tertiary>secondary>primary
What are addition polymers formed from? - correct answers-Alkenes and substituted
alkenes
answers
Relative atomic mass (Ar) - correct answers-Average mass of an atom compared with
one twelth of the mass of an atom of carbon 12
Electronegativity - correct answers-Power of an atom to attract the pair of electrons in a
covalent bond
Standard enthalpy of combustion - correct answers-Enthalpy change when 1 mole of a
substance burns completely in oxygen under standard conditions with all reactants and
products being in their standard state
Standard enthalpy of formation - correct answers-Enthalpy change when 1 mole of a
compound is formed from it's elements under standard conditions in their standard
states
Mean bond enthalpy - correct answers-The average energy needed to break a certain
type of bond over a range of compounds
Activation energy - correct answers-Minimum energy required for colliding molecules to
react
Maxwell-Boltzmann distribution x and y axes - correct answers-x: Energy
y: fraction/number of molecules
What happens to the Maxwell-Boltzmann curve when temperature increases - correct
answers-Moves down and to the right
Rate of reaction - correct answers-Rate at which product formed/reactant used up
Order of reaction - correct answers-Power to which the concentration of a species is
raised in the rate equation
rearrange k=Ae^-Ea/Rt - correct answers-lnk=-Ea/Rt+lnA
Conditions for thermal cracking - correct answers-High temperature and high pressure
Products of thermal cracking - correct answers-High % of alkenes
Conditions for catalytic cracking - correct answers-High temperature ,slight pressure
and in the presence of a zeolite catalyst
Products of catalytic cracking - correct answers-Motor fuels and aromatic hydrocarbons
, Why do we crack alkanes? - correct answers-Smaller alkanes/alkenes generally more
useful than longer chain ones
Equation for complete combustion of alkanes - correct answers-alkane + oxygen >
carbon dioxide + water
Equations for incomplete combustion of alkanes - correct answers-alkane + oxygen >
carbon monoxide/carbon + water
Pollutants produced by combustion engines - correct answers-NOx, CO, C and
sunburned hydrocarbons
Reaction of methane with chlorine - correct answers-I: Cl2 > 2Cl•
P: CH4 + Cl• > CH3• + Chi
CH3• + Cl2 > CH3Cl + Cl•
T: CH3• + Cl• > CH3Cl
2 equations showing decomposition of the ozone - correct answers-Cl• + O3 > ClO• +
O2
ClO• + O3 > 2O2 + Cl•
What types of mechanism do haloalkanes undergo? - correct answers--Nucleophilic
substitution by aqueous hydroxide ions, cyanide ions or ammonia
-Elimination with ethanolic hydroxide ions
What type of mechanism do alkenes undergo? - correct answers-Electrophilic addition
by bromine, hydrogen bromide or sulphuric acid
Test for primary or secondary alcohols - correct answers-Warm with acidified potassium
dichromate (VI) and positive result is Solution turning green
Tests for aldehyde or ketone - correct answers--Warm with Fehlings Solution - brick red
precipitate indicates aldehyde
-Warm with Tollens reagent (silver nitrate + sodium hydroxide + dilute ammonia) -
aldehyde gives a silver mirror
Test for alkenes - correct answers-Shake with bromine water- alkene goes from Orange
to colourless
Test for carboxylic acids - correct answers-Sodium carbonate and effervescence is
positive
Relative stabilities of carbocations - correct answers-tertiary>secondary>primary
What are addition polymers formed from? - correct answers-Alkenes and substituted
alkenes
