Transcript Unit 5 and 6 revsion

Standard Grade Revision
Units 5 and 6
Q1. Crude oil is an example of a fossil fuel.
(a) What is meant by the term ‘fuel’?
(b) Name two other fossil fuels.
(c) Describe how crude oil is formed.
(a) A chemical which burns giving out energy.
(b) Coal and natural gas.
(c) Formed from dead sea animals. Remains buried under layers of rock
for millions of years. Heat and pressure changed remains into oil.
Q2. What are the tests for
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(a) Oxygen
(a) Relights a glowing splint.
(b) Carbon dioxide.
(b) Turns lime water chalky (milky).
(c) Hydrogen.
(c) Burns with a ‘pop’
Units 5 and 6 Revision
Q3. Which gas makes up
(a) about 80% of the air?
(a) Nitrogen.
(b) about 20% of the air?
(b) Oxygen.
Q4. The fossil fuels are a finite resource.
What is meant by the term ‘finite resource’?
A finite resource is a substance whose supply will run out in the future.
Q5. The word box gives the formulae of some oxides.
H2O
NO2
K2 O
CaO
CO
SO2
(a) Identify the oxide produced by the sparking of air in car engines.
(b) Identify the two oxides produced by burning hydrocarbons.
(c) Identify the two oxides which are mainly responsible for acid rain.
(a) NO2.
(b) H2O
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and
(c) NO2 and SO2.
CO.
Units 5 and 6 Revision
Q6. The word box shows the formulae of some hydrocarbon compounds.
CH4
C2H4
C6H14
C5H12
C3H8
C4H8
(a) Identify the molecular formula for pentane.
(b) Identify the two molecular formulae which represent alkenes
(c) Identify the hydrocarbon which has a boiling point of 69oC.
(You may want to use page 6 of the data booklet to help you).
(d) Identify the two hydrocarbons formed when propane is cracked.
(a) C5H12
C2H4.
(b) C2H4 and C4H8
(c) C6H14
(d) CH4 and
Q7. The word box shows the names of some hydrocarbons.
cyclobutane
propane
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cyclopentane
ethane
butane
butene
(a) Identify the hydrocarbon which is a liquid at 25oC.
(b) Identify the two isomers.
(c) Identify the hydrocarbon that reacts quickly with
bromine solution.
(a) Cyclopentane
(b) Cyclobutane
and butene
(c) butene.
Units 5 and 6 Revision.
Q8. Hexane can be cracked using aluminium oxide as the catalyst
Mineral wool
soaked in hexane
One of the reactions taking place is
C6H14  C2H4 + X
(a) Draw the structural formula for hexane.
(a)
(b) Write the molecular formula for X.
(b) C4H10
(c) Name the product C2H4.
(c) Ethene
(d) Aluminium oxide is a white solid but at the end of the experiment it
is covered with a black substance.
Suggest what the black substance could be.
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(d) Carbon (soot)
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Units 5 and 6 Revision.
Q9.
Dienes are a homologous series of hydrocarbons which contain two double
bonds per molecule.
(a) What is meant by the term “homologous series”?
(a)
(b) Suggest a general formula for the dienes.
(c) Write the molecular formula for the product of the complete (b)
(c)
reaction of penta-1,3-diene with bromine.
(d) Draw the full structural formula for an isomer of
buta-1,3-diene which contains only one double bond
per molecule.
(d)
Family of compounds with same general
formula.
CnH2n-2.
C5H8Br4.
Q10. The diagram shows the names and boiling ranges of some of the fractions which are
obtained from crude oil.
(a) Name the process which is used to separate the crude
(a) Fractional distillation.
oil into fractions.
(b) As shown in the diagram is
(i) flammability increasing or decreasing?
(b) (i) Increasing
(ii) Decreasing.
(ii) viscosity increasing or decreasing?
(c) Gases.
(c) ) In which fraction is propane found?
(Use your data booklet)
(d) Decane is a compound found in the kerosene fraction.
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To which family of hydrocarbons does decane belong?
(d) Alkanes.
Units 5 and 6 Revision.
Q11. The alkanes are saturated hydrocarbons. The alkenes
are unsaturated hydrocarbons.
(a) What is meant by the term ‘saturated’?
(b) What is meant by the term ‘unsaturated’?
(c) What is the general formula of the
(i) alkanes?
(ii) alkenes?
(d) Describe a chemical test that can be used to
distinguish between alkanes and alkenes.
(a) Saturated means the compound contains only single C-C bonds.
(b) Unsaturated means the compound contains a C=C double bond.
(c) (i) Alkane general formula is CnH2n+2.
(ii) Alkenes general formula is CnH2n.
(d) Alkanes do not immediately decolourise bromine solution.
Alkenes immediately decolourise bromine solution.
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Units 5 and 6 Revision.
Q12. Hydrocarbons are compounds which contain hydrogen and carbon only.
(a)
Which box (A to E) shows the hydrocarbon which reacts with hydrogen
to form butane.
(b)
Which two boxes show hydrocarbons which are isomers.
(c)
Which two boxes show hydrocarbons which are the first members of a
homologous series
(a) Box F
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(b) Boxes C and D
(c) Boxes A and C
Units 5 and 6 Revision.
Q13. Propene has the structural formula shown below.
Propene quickly decolourises bromine water, Br2(aq).
(a) Name the type of chemical reaction which takes place when propene reacts
with bromine water.
(b)
Draw the full structural formula for the product of the reaction.
(c)
Write a balanced equation for the complete combustion of propene.
(a) Addition.
(b)
Br
Br H
H – C – C – C –H
H H H
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(c) 2C3H6 + 9O2  6CO2 + 6H2O
Units 5 and 6 Revision.
Q14. The burning of fossil fuels is a major source of air pollution.
(a) Name the acidic gas formed when air in a car engine is sparked.
(b) Name the acidic gas formed when coal with a high sulphur
content is burned.
(c) Name the toxic gas formed when methane is burned in a limited
supply of air.
(d) A catalytic converter fitted to a car exhaust reduces the amount
of dangerous gases emitted into the atmosphere. Name the
catalyst used in a catalytic converter.
(a) Oxides of nitrogen such as nitrogen dioxide.
(b) Sulphur dioxide.
(c) Carbon monoxide.
(d) Platinum.
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