AQA A-Level Chemistry Paper 2 Exam
Witl All Correct Answers Passed!!!
(A+)
Relative atomic mass (Ar) - Ans--Average mass of an atom compared with
one twelth of the mass of an atom of carbon 12
Electronegativity - Ans--Power of an atom to attract the pair of electrons in a
covalent bond
Standard enthalpy of combustion - Ans--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 - Ans--Enthalpy change when 1 mole of a
compound is formed from it's elements under standard conditions in their
standard states
Mean bond enthalpy - Ans--The average energy needed to break a certain
type of bond over a range of compounds
Activation energy - Ans--Minimum energy required for colliding molecules to
react
Maxwell-Boltzmann distribution x and y axes - Ans--x: Energy
y: fraction/number of molecules
What happens to the Maxwell-Boltzmann curve when temperature
increases - Ans--Moves down and to the right
Rate of reaction - Ans--Rate at which product formed/reactant used up
Order of reaction - Ans--Power to which the concentration of a species is
raised in the rate equation
, rearrange k=Ae^-Ea/Rt - Ans--lnk=-Ea/Rt+lnA
Conditions for thermal cracking - Ans--High temperature and high pressure
Products of thermal cracking - Ans--High % of alkenes
Conditions for catalytic cracking - Ans--High temperature ,slight pressure
and in the presence of a zeolite catalyst
Products of catalytic cracking - Ans--Motor fuels and aromatic hydrocarbons
Why do we crack alkanes? - Ans--Smaller alkanes/alkenes generally more
useful than longer chain ones
Equation for complete combustion of alkanes - Ans--alkane + oxygen >
carbon dioxide + water
Equations for incomplete combustion of alkanes - Ans--alkane + oxygen >
carbon monoxide/carbon + water
Pollutants produced by combustion engines - Ans--NOx, CO, C and
sunburned hydrocarbons
Reaction of methane with chlorine - Ans--I: Cl2 > 2Cl•
P: CH4 + Cl• > CH3• + Chi
CH3• + Cl2 > CH3Cl + Cl•
T: CH3• + Cl• > CH3Cl
2 equations showing decomposition of the ozone - Ans--Cl• + O3 > ClO• + O2
ClO• + O3 > 2O2 + Cl•
What types of mechanism do haloalkanes undergo? - Ans---Nucleophilic
substitution by aqueous hydroxide ions, cyanide ions or ammonia
-Elimination with ethanolic hydroxide ions
What type of mechanism do alkenes undergo? - Ans--Electrophilic addition
by bromine, hydrogen bromide or sulphuric acid
Witl All Correct Answers Passed!!!
(A+)
Relative atomic mass (Ar) - Ans--Average mass of an atom compared with
one twelth of the mass of an atom of carbon 12
Electronegativity - Ans--Power of an atom to attract the pair of electrons in a
covalent bond
Standard enthalpy of combustion - Ans--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 - Ans--Enthalpy change when 1 mole of a
compound is formed from it's elements under standard conditions in their
standard states
Mean bond enthalpy - Ans--The average energy needed to break a certain
type of bond over a range of compounds
Activation energy - Ans--Minimum energy required for colliding molecules to
react
Maxwell-Boltzmann distribution x and y axes - Ans--x: Energy
y: fraction/number of molecules
What happens to the Maxwell-Boltzmann curve when temperature
increases - Ans--Moves down and to the right
Rate of reaction - Ans--Rate at which product formed/reactant used up
Order of reaction - Ans--Power to which the concentration of a species is
raised in the rate equation
, rearrange k=Ae^-Ea/Rt - Ans--lnk=-Ea/Rt+lnA
Conditions for thermal cracking - Ans--High temperature and high pressure
Products of thermal cracking - Ans--High % of alkenes
Conditions for catalytic cracking - Ans--High temperature ,slight pressure
and in the presence of a zeolite catalyst
Products of catalytic cracking - Ans--Motor fuels and aromatic hydrocarbons
Why do we crack alkanes? - Ans--Smaller alkanes/alkenes generally more
useful than longer chain ones
Equation for complete combustion of alkanes - Ans--alkane + oxygen >
carbon dioxide + water
Equations for incomplete combustion of alkanes - Ans--alkane + oxygen >
carbon monoxide/carbon + water
Pollutants produced by combustion engines - Ans--NOx, CO, C and
sunburned hydrocarbons
Reaction of methane with chlorine - Ans--I: Cl2 > 2Cl•
P: CH4 + Cl• > CH3• + Chi
CH3• + Cl2 > CH3Cl + Cl•
T: CH3• + Cl• > CH3Cl
2 equations showing decomposition of the ozone - Ans--Cl• + O3 > ClO• + O2
ClO• + O3 > 2O2 + Cl•
What types of mechanism do haloalkanes undergo? - Ans---Nucleophilic
substitution by aqueous hydroxide ions, cyanide ions or ammonia
-Elimination with ethanolic hydroxide ions
What type of mechanism do alkenes undergo? - Ans--Electrophilic addition
by bromine, hydrogen bromide or sulphuric acid
