OCR B Salters A Level Chemistry –
Comprehensive Revision Questions and
Answers, UK A Level Chemistry
Introduction:
This document contains an extensive collection of OCR B
Salters A Level Chemistry revision questions with clear,
concise answers covering physical, organic, and inorganic
chemistry. Topics include energetics, kinetics, equilibrium,
redox, electrolysis, atomic structure, bonding, organic reaction
mechanisms, fuels, the atmosphere, and analytical tests,
making it ideal for exam revision and knowledge
consolidation. The content is well suited for OCR B Salters
specification students preparing for mocks, final exams, or
quick topic-by-topic review.
Exam Questions and Answers:
How is photochemical smog formed? -Answer:-When nitrogen
oxides and volatile organic hydrocarbons react with heat and
sunlight to produce a variety of pollutants
How does sulfur dioxide cause acid rain? -Answer:-Some SO2
reacts with water to form weak sulfuric(IV) acid. Some SO2 is
,oxidised to SO3, which reacts which water in the atmosphere
to form the strong acid sulfuric(VI) acid
What is photochemical smog? -Answer:-A mixture of primary
and secondary pollutants formed under the influence of UV
radiation from the sun, causes haziness and breathing
problems
What is trosphospheric ozone? -Answer:-Action of sunlight on
NO causes photodissociation so an O radical forms. O radical
reacts with O2 molecules.
What are the three main pollutants removed by catalytic
converters in petrol engines and give their equations -
Answer:-1) Carbon monoxide: 2CO + O2 --> CO2
2) Hydrocarbons: C7H16 + 11O2 --> 7CO2 +8H2O
3) Nitrous oxides: 2NO + CO --> N2 + 2CO2
How are sulfur oxide pollutants prevented -Answer:-Removing
sulfur impurities from fuels before the motorist uses them
What metals can be used is catalytic converters? -Answer:-
Platinum and Rhodium on a porous support
,How are particulates captured by diesel engines? -Answer:-
Particulate filters containing ceramic or regeneration (burning
off carbon particles using higher temp, which increases fuel
consumption)
Why can't oxides of nitrogen be removed by a catalytic
converter in a diesel engine? -Answer:-Excess of oxygen in
exhaust so NO cannot be reduced
2 ways oxides of nitrogen are removed from diesel engines? -
Answer:--Lowering the temperature
-Reacting with ammonia in the presence of a catalyst
4NO + 4NH3 + O2 --> 4N2 + 6H20
Explain the trend in the melting point of metals across the
period -Answer:-Melting point increases across the period
because
.More delocalised electrons
.Ionic radius decreases because electrons are pulled closer to
heavier nucleus, so charge density increases
.So stronger metal-metal bonds
, metal oxide + water -Answer:-metal hydroxide + hydrogen
Thermal decomposition of metal carbonates -Answer:-metal
carbonate --> metal oxide + carbon dioxide
Why does Mg have a higher melting point than Na -Answer:--
More delocalised electrons
-Higher charge density
-Stronger metal-metal bonds
Explain the first ionization enthalpy trend of Group 2 -
Answer:-Decreases down the group because outer electron is
further away from nucleus and more filled shells means more
shielding, decreasing nuclear attraction
Carbonate Ion bond angle -Answer:-
Equation for first ionisation enthalpy of hydrogen -Answer:-H
(g) --> H+ (g) + e-
.MUST INCLUDE STATE SYMBOLS
Comprehensive Revision Questions and
Answers, UK A Level Chemistry
Introduction:
This document contains an extensive collection of OCR B
Salters A Level Chemistry revision questions with clear,
concise answers covering physical, organic, and inorganic
chemistry. Topics include energetics, kinetics, equilibrium,
redox, electrolysis, atomic structure, bonding, organic reaction
mechanisms, fuels, the atmosphere, and analytical tests,
making it ideal for exam revision and knowledge
consolidation. The content is well suited for OCR B Salters
specification students preparing for mocks, final exams, or
quick topic-by-topic review.
Exam Questions and Answers:
How is photochemical smog formed? -Answer:-When nitrogen
oxides and volatile organic hydrocarbons react with heat and
sunlight to produce a variety of pollutants
How does sulfur dioxide cause acid rain? -Answer:-Some SO2
reacts with water to form weak sulfuric(IV) acid. Some SO2 is
,oxidised to SO3, which reacts which water in the atmosphere
to form the strong acid sulfuric(VI) acid
What is photochemical smog? -Answer:-A mixture of primary
and secondary pollutants formed under the influence of UV
radiation from the sun, causes haziness and breathing
problems
What is trosphospheric ozone? -Answer:-Action of sunlight on
NO causes photodissociation so an O radical forms. O radical
reacts with O2 molecules.
What are the three main pollutants removed by catalytic
converters in petrol engines and give their equations -
Answer:-1) Carbon monoxide: 2CO + O2 --> CO2
2) Hydrocarbons: C7H16 + 11O2 --> 7CO2 +8H2O
3) Nitrous oxides: 2NO + CO --> N2 + 2CO2
How are sulfur oxide pollutants prevented -Answer:-Removing
sulfur impurities from fuels before the motorist uses them
What metals can be used is catalytic converters? -Answer:-
Platinum and Rhodium on a porous support
,How are particulates captured by diesel engines? -Answer:-
Particulate filters containing ceramic or regeneration (burning
off carbon particles using higher temp, which increases fuel
consumption)
Why can't oxides of nitrogen be removed by a catalytic
converter in a diesel engine? -Answer:-Excess of oxygen in
exhaust so NO cannot be reduced
2 ways oxides of nitrogen are removed from diesel engines? -
Answer:--Lowering the temperature
-Reacting with ammonia in the presence of a catalyst
4NO + 4NH3 + O2 --> 4N2 + 6H20
Explain the trend in the melting point of metals across the
period -Answer:-Melting point increases across the period
because
.More delocalised electrons
.Ionic radius decreases because electrons are pulled closer to
heavier nucleus, so charge density increases
.So stronger metal-metal bonds
, metal oxide + water -Answer:-metal hydroxide + hydrogen
Thermal decomposition of metal carbonates -Answer:-metal
carbonate --> metal oxide + carbon dioxide
Why does Mg have a higher melting point than Na -Answer:--
More delocalised electrons
-Higher charge density
-Stronger metal-metal bonds
Explain the first ionization enthalpy trend of Group 2 -
Answer:-Decreases down the group because outer electron is
further away from nucleus and more filled shells means more
shielding, decreasing nuclear attraction
Carbonate Ion bond angle -Answer:-
Equation for first ionisation enthalpy of hydrogen -Answer:-H
(g) --> H+ (g) + e-
.MUST INCLUDE STATE SYMBOLS
