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Ethene is prepared in the laboratory by dehydration of ethanol.
Expected Response
A monomer has the following structure.
(a) Draw the structure of its polymer that contains three monomers. (1 mark)
(b) A sample of the polymer formed from the monomer has a molecular mass of 4992. Determine the number of monomers that formed the polymer (C= 12; H= 1.0). (2 marks)
Expected Response
a
b
(a) Draw and name the isomers of butyne
(b) State one use of polystyrene.
ANSWERS
(b)Used in packaging - cushions electronics in boxes/insulation/models/ceiling strips/crates or binding.
In the presence of U.V light, ethane gas undergoes substitution reaction with chlorine.
(a) What is meant by the term? Substitution reaction: (b) Give the structural formula and the name of the organic product formed when equal volumes of ethane and chlorine react together.
Expected Response
Study the flowchart below and answer the questions that follow:
(a) Identify:
(i) X (ii) Y (b) State two uses of polyvinylchloride
ANSWERS
Draw and name the isomers of pentane.
ANSWERS
A hydrocarbon P was found to decolourise bromine water. On complete combustion of 2 moles of P, 6 moles of carbon dioxide and 6 moles of water were formed
Expected Response
Exhaust fumes of some cars contain carbon(II)oxide and other gases.
(a) Explain how carbon (II) oxide is formed in the internal combustion engines. (b) Name two gases other than carbon (II) oxide that are contained in exhaust fumes and are pollutants.
ANSWERS
(a) Carbon (II) oxide is formed in the internal combustion engines when fuel burns under limited oxygen.
(b) Pollutant gas - Carbon (IV) oxide, Nitrogen (1V) oxide and Sulphur (IV) oxide.
Draw the structures and give the name of the three alkaline having molecular formula C5H10
ANSWERS
The figure below represents the set up that was used to crack an alkane.
a) What was the purpose of the sand?
b) After some time, a colourless gas G collected in the test-tube. Describe a chemical test and the observations that would be made in ordered to identify the class of compounds to which gas G belongs.
ANSWERS
(a) Catalyst or words to that effect
(b) Add bromine water or acidified potassium magnate (VII) if they decolorize then gas is either an alkene or an alkynes
A hydrocarbon slowly decolorizes bromine gas in the presence of sunlight but does not decolourise acidified potassium permanganate
Name and draw the structural formula of the fourth member of the series to which the hydrocarbon belongs.
Expected Response
a) Draw and name the structure of the compound formed when one mole of ethyne reacts with one mole of hydrogen bromide.
b) Draw the structures of the alkynes whose molecular formula is C4H6
ANSWERS
The formula given below represents a portion of a polymer Give:
Expected Response
(a) Give the names of the following compounds
(b) Study the information in the table below and answer the questions that follow
(i) Name the reagents used in:
Step I ……………………. Step II …………………….. Step III …………………….. (ii) Write an equation for the complete combustion of CH = CH (iii) Explain one disadvantage of the continued use of items made from the compound formed in step III
Expected Response
The relative formula mass of a hydrocarbon is 58. Draw and name two possible structures of the hydrocarbon (C=12.0; H=1.0)
ANSWERS
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December 2024
AuthorMaurice Atika is a teacher and a netprenuer. |
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