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The diagram below represents an in complete set-up for preparation of a dry sample of gas R
a) Complete the set-up to show how a dry sample of gas R is collected
b) Write a chemical equation for the reaction that produces gas R
Date posted:
October 22, 2019
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The diagram below is a set-up used in preparation of ammonia solution. Study it and answer the questions that follow
(i) What is the purpose of the filter funnel in the set-up above?
(ii) What would happen if a delivery tube was used in place of the filter funnel?
(iii) What observation would be made on litmus paper placed into the solution in the beaker at the end of the experiment?
Date posted:
October 22, 2019
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The diagram below is a set-up for preparation and collection of a gas. Study it answer the questions that follow:
(i) Identify gas X
(ii) Write an equation for the formation of gas X
(iii) What precaution should be observed when preparing gas X by the above method?
(iv) Describe the suitable drying agent for gas X
(v) How can one confirm that the gas collected is gas X?
(vi) State two physical properties of gas X
Date posted:
October 22, 2019
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The chart below shows a summary for the preparation of nitrogen gas from air
(a) What is the purpose of the sodium hydroxide?
(b) Write an equation for the reaction taking place in chamber II
(c) The nitrogen gas obtained is not pure. Explain
Date posted:
October 22, 2019
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A mixture of N2, H2 and NH3 was bubbled through 0.2M hydrochloric acid solution.
The final concentration of the acid was found to be 0.1M. Give explanation
Date posted:
October 22, 2019
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Study the flow charts below and use them to answer the questions that follow:
(a) Identify possible cations present in:
(i) Solution A
(ii) Solution B
(b) State and explain the observations made when a sample of dry white precipitate B is heated in a test-tube
Date posted:
October 22, 2019
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The diagram below is used in preparation of a gas in the laboratory. Answer the questions that follow;
(a) Name gas X
(b) State one physical property which makes it possible for the gas to be collected as shown
(c) State one commercial use of gas X
Date posted:
October 22, 2019
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(a) Explain the importance of the high percentage of nitrogen in air
(b) Why is nitrogen used for storage of semen in artificial insemination?
Date posted:
October 22, 2019
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Ammonia gas is prepared in the laboratory by the action of an alkali on an ammonium salt.
A student wanted to prepare a sample of ammonia gas in the laboratory.
(a) Give one alkali that can be used in the above experiment
(b) Write an equation for the reaction that takes place in the above experiment
Date posted:
October 22, 2019
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The diagram below shows the catalytic oxidation of ammonia gas. Use it to answer the questions that follow:-
(a) What metal could rod M be made of?
(b) State and explain two observations made inside the conical flask
Date posted:
October 22, 2019
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A hydrocarbon compound Z decolourizes bromine liquid in the presence of light but does not decolourize acidified potassium manganate (VII). Name and draw the structural formula of the eighth member of this homologous series
Date posted:
October 22, 2019
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Write down all the isomers of but-z-ene and give their IUPAC names
Date posted:
October 22, 2019
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(i) 2.63g of a solution of sodium chloride at 20.0oC was reacted with silver nitrate. After filtration,washing and drying, 2.36g of silver chloride was obtained. Determine the solubility of sodium
chloride at 20.0oC . (Na=23, Cl= 35.5, Ag = 108)
(ii) Determine the number of moles of carbon (IV) Oxide gas produced when sodium carbonate reacted with dilute sulphuric (VI) acid (Molar gas volume =24dm3)
Date posted:
October 22, 2019
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Substance “M” with a general formula C2Hy burnt in chlorine gas with a red flame producing a cloud of black specks and colourless gas G.
(a) State the collective name for compounds which ‘M’ belongs
(b) With reason, state the identity of the black specks and colour gas “G”.
Date posted:
October 22, 2019
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Study the data given in the following table and answer the questions that follow. The letters are not the actual symbols of elements.
(i) State and explain the trend in melting point in A B C
(ii) Explain why the melting point and boiling points of element D is the highest
(iii) Explain why the element represented by letter E has two melting point values
(iv) Write down the chemical formula between element C and sulphate ions
(v) Name the chemical family in which H belong and state one use of the element
(vi) What is the nature of the oxide of the elements represented by letters C and F?
Date posted:
October 22, 2019
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Give the systematic names of the following compounds;
Date posted:
October 22, 2019
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Study the scheme below and answer the questions that follow:
Name the reagents in
Step I
Step II
Step IV
(ii) Write an equation for the complete combustion of 
(iii) Give two uses of CH4
Date posted:
October 22, 2019
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Ethene is used in making polyethene bag in a process called polymerization
(i) Name the type of polymer that is formed when ethane polymerise
(ii) Describe a simple chemical test that can be used to identify ethane gas in the laboratory
Date posted:
October 22, 2019
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Name the following compounds:(CH3)3 C CH2 CH2 CH3
Date posted:
October 22, 2019
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Give two ways how the disposal of polymers such as polychloroethene by burning pollutes the environment
Date posted:
October 22, 2019
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State the observations made when buton-l-ol reacts with:-
(i) Acidified potassium dichromate (VI) solution
(ii) Potassium metal
Date posted:
October 22, 2019
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Give the systematic names of the following compounds:-
Date posted:
October 22, 2019
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Use the diagram below to answer the questions that follow:
(i) Name another source of hydrogen apart from electrolysis of water
(ii) What conditions are necessary for step III to occur?
(iii) Write the equation for the formation of colourless gas Q
Date posted:
October 22, 2019
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Given the reaction:
(i) Identify substance and F and N
(ii) Name the process represented above?
(iii) Give one use of substance N
Date posted:
October 18, 2019
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The set-up below was used to prepare ethyne gas
(i) Identify solid E
(ii) Complete the diagram to show how the gas can be collected
(iii) Write an equation to show how the gas is formed
(iv) Complete the equation below: )
C2H2 + 2I2---------------->
(v) What is the role of sand in the experiment?
Date posted:
October 18, 2019
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The diagram below represents a large-scale fractional distillation plant used to separate the components A, B, C and D in a mixture
The components have the following average relative molecular masses not necessarily in that
order; 282, 184, 44 and 128.
(i) What is the physical state of B at the position marked Q?
(ii) Which component has an average relative molecular mass of 128? Explain
(iii) State with a reason whether C is pure or impure
(iv) Explain how the mixture is separated into its components
(v) Name two naturally occurring mixtures that are separated using this process
Date posted:
October 18, 2019
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Give the open structures of:-
(i) 3-chlorohex-l-yne
(ii) CH3OH
Date posted:
October 18, 2019
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10cm3 of methane (CH4) gas is exploded with 150cm3 of air containing 20% oxygen and 80% nitrogen. The products were allowed to cool to room temperature. What will be the total volume of the gases at the end of the reaction?
Date posted:
October 17, 2019
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Polymerisation of ethene takes place as shown in the equation below:
Name the type of polymerisation undergone by ethene in the reaction above
Date posted:
October 17, 2019
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Distinguish between the isotopes and isomers
Date posted:
October 17, 2019