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A student set up the apparatus shown below to prepare and collect dry carbon (IV) oxide gas.
(Solved)
A student set up the apparatus shown below to prepare and collect dry carbon (IV) oxide gas.

State a correction for three mistakes in the set up above
Date posted:
March 28, 2019
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Answers (1)
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Zinc reacts with both concentrated and dilute sulphuric (VI) acid. Write equations for the two reactions.
(Solved)
Zinc reacts with both concentrated and dilute sulphuric (VI) acid. Write equations for the two reactions.
Date posted:
March 28, 2019
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Answers (1)
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When a hydrated sample of calcium sulphate CaSO4.xH2O was heated until all the water was lost, the following data was recorded:
Mass of crucible = 30.296...
(Solved)
When a hydrated sample of calcium sulphate CaSO4.xH2O was heated until all the water was lost, the following data was recorded:
Mass of crucible = 30.296 g
Mass of crucible + hydrated salt = 33.111 g
Mass of crucible + anhydrous salt = 32.781 g
Determine the empirical formula of the hydrated salt
(CA = 40, S = 32, O = 16 H = 1)
Date posted:
March 28, 2019
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Answers (1)
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The set up of diagram shown below is used to prepare dry nitrogen gas from air. Study it and answer the questions that follow.
(Solved)
The set up of diagram shown below is used to prepare dry nitrogen gas from air. Study it and answer the questions that follow.

(a) What is the purpose of using:
(i) A burning candle.
(ii) Sodium hydroxide solution.
(b) Name:
(i) One impurity present in nitrogen gas prepared.
(ii) A suitable drying agent used.
Date posted:
March 28, 2019
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Answers (1)
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The set-up below was used to prepare dry chlorine gas. Study and answer the questions that follow
(Solved)
The set-up below was used to prepare dry chlorine gas. Study and answer the questions that follow

(a) Name reagents M and substance L.
(b) A warm red phosphorus was lowered into the gas jar of chlorine using a deflagrating spoon:
(i) State any one observation made in this experiment.
(ii) Identify the substance formed in the above reaction.
(c) Both substances in (ii) above undergo hydrolysis when exposed to air. Write an equation to show how anyone of them undergoes hydrolysis.
Date posted:
March 28, 2019
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Answers (1)
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Cyanogen is a gaseous compound of carbon and nitrogen only. On complete combustion in oxygen, 250cm3 of cyanogen form 500cm3 of Carbon (IV) Oxide and...
(Solved)
Cyanogen is a gaseous compound of carbon and nitrogen only. On complete combustion in oxygen, 250cm3 of cyanogen form 500cm3 of Carbon (IV) Oxide and 250cm3 of nitrogen. Determine the formula of cyanogen.
Date posted:
March 28, 2019
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Answers (1)
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State two properties that vulcanized rubber possesses as a result of vulcanization.
(Solved)
State two properties that vulcanized rubber possesses as a result of vulcanization.
Date posted:
March 28, 2019
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Answers (1)
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Write an ionic equation for the reaction between copper II ions in solution and excess ammonia solution.
(Solved)
Write an ionic equation for the reaction between copper II ions in solution and excess ammonia solution.
Date posted:
March 28, 2019
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Answers (1)
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Give two reasons why luminous flame is not used for heating purposes in the laboratory.
(Solved)
Give two reasons why luminous flame is not used for heating purposes in the laboratory.
Date posted:
March 28, 2019
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Answers (1)
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The diagram below shows some properties of ammonia gas. Use it to answer the questions that follow
(Solved)
The diagram below shows some properties of ammonia gas. Use it to answer the questions that follow

a) State the observation made in the combustion tube.
b) (i) Give the test that can be used to identify liquid Y.
(ii) Name gas X
Date posted:
March 27, 2019
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Answers (1)
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The set up was used to prepare dry hydrogen gas. Study it and answer the questions that follow.
(Solved)
The set up was used to prepare dry hydrogen gas. Study it and answer the questions that follow.

i) Is set-up used to prepare the gas correct? Give reason.
(ii) What would be liquid Y?
(iii) Give two physical properties of hydrogen gas
Date posted:
March 27, 2019
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Answers (1)
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Relative molecular mass of methane and water are almost similar, however the boiling of water is 1000C while that of methane is -1610C. Explain.
(Solved)
Relative molecular mass of methane and water are almost similar, however the boiling of water is 1000C while that of methane is -1610C. Explain.
Date posted:
March 27, 2019
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Answers (1)
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The structure of water molecules can be represented as shown below.
(Solved)
The structure of water molecules can be represented as shown below.

Name the bond type represented by letter X and W.
Date posted:
March 27, 2019
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Answers (1)
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The diagram below shows spots of pure substances A, B and C on a chromatography paper. Spot D is that of a mixture.
(Solved)
The diagram below shows spots of pure substances A, B and C on a chromatography paper. Spot D is that of a mixture.

After development, A, B and C were found to have moved 8cm, 3cm and 6cm respectively. D had separated into two spots which had moved 6cm and 8cm.
(i) On the diagram
I. Label baseline
II. Show the positions of all the spots after development.
(ii) Identify the substances present in the mixture D.
Date posted:
March 27, 2019
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Answers (1)
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Use the information given below to draw the energy cycle diagram for the enthalpy of formation of propane.
(Solved)
Use the information given below to draw the energy cycle diagram for the enthalpy of formation of propane.

Date posted:
March 27, 2019
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Answers (1)
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The PH of a soil sample was found to be 5.7. An agricultural officer recommended addition of lime.
(a) State two functions of the lime.
(b)...
(Solved)
The PH of a soil sample was found to be 5.7. An agricultural officer recommended addition of lime. State two functions of the lime.
Date posted:
March 27, 2019
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Answers (1)
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An element X has a relative atomic mass of 88. When a current of 0.5 ampere was passed through a fused chloride of X for...
(Solved)
An element X has a relative atomic mass of 88. When a current of 0.5 ampere was passed through a fused chloride of X for 32 minutes 10 seconds, 0.44g of X was deposited.
(i) Determine the charge of element X [1 Faraday = 96500C]
(ii) Write the formula of hydroxide of X
Date posted:
March 27, 2019
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Answers (1)
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A form two student in an attempt to prevent rusting put copper and zinc in contact with iron as shown below.
(Solved)
A form two student in an attempt to prevent rusting put copper and zinc in contact with iron as shown below.

(i) State what would happen in set up X and Y after one week.
(ii) Explain your answer in diagram Y.
Date posted:
March 27, 2019
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Answers (1)
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Volume of liquids can be measured using a pipette; measuring cylinder or burette. Explain which one would be best for measuring 29.1cm3 of liquid.
(Solved)
Volume of liquids can be measured using a pipette; measuring cylinder or burette. Explain which one would be best for measuring 29.1cm3 of liquid.
Date posted:
March 27, 2019
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Answers (1)
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0.318g of an oxide of metal M was completely reduced by hydrogen gas to 0.254g of metal. Calculate empirical formula of the metal oxide. (M...
(Solved)
0.318g of an oxide of metal M was completely reduced by hydrogen gas to 0.254g of metal. Calculate empirical formula of the metal oxide. (M = 63.5, O = 16)
Date posted:
March 27, 2019
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Answers (1)