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The solubility of copper (II) sulphate is 55g/100g of water at 75oC and 19g/100g of
water at 15oC. What mass of crystals would be deposited, if...
(Solved)
The solubility of copper (II) sulphate is 55g/100g of water at 75oC and 19g/100g of
water at 15oC. What mass of crystals would be deposited, if 150g of a saturated solution
is cooled from 75oC to 15oC.
Date posted:
May 22, 2019
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Answers (1)
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Reagent bottles labelled H2SO4 solution, K2CO3 solution and NaCl solution had labels
accidentally removed. A packet of blue litmus paper is lying near a long with...
(Solved)
Reagent bottles labelled H2SO4 solution, K2CO3 solution and NaCl solution had labels
accidentally removed. A packet of blue litmus paper is lying near a long with a rack of test-tubes, without using any other material explain how you would go about labeling the bottles correctly.
Date posted:
May 22, 2019
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Answers (1)
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The scheme below shows a reaction sequence starting with solid N. study it and answer
the questions that follows.
a) Name the cation present in solid N....
(Solved)
The scheme below shows a reaction sequence starting with solid N. study it and answer
the questions that follows.
a) Name the cation present in solid N.
b) Write the formula of the complex ion in the colorless solution Q.
c) Write an ionic equation for the reaction in step 2.
Date posted:
May 22, 2019
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Answers (1)
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What is meant by the term strong acid?
(Solved)
What is meant by the term strong acid?
Date posted:
May 22, 2019
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Answers (1)
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The set-up below was used to prepare Nitric(V) acid in the laboratory.
a) Name liquid T.
b) Write an equation for the reaction taking place in the...
(Solved)
The set-up below was used to prepare Nitric(V) acid in the laboratory.
a) Name liquid T.
b) Write an equation for the reaction taking place in the flask.
c) State the reason why nitric (V) acid collected is brown in colour and explain how the
brown colour can be removed.
Date posted:
May 22, 2019
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Answers (1)
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The empirical formula of a compound is C2H5. When 11.6g of the compound was
allowed to evaporate; it occupied 4.8 dm3 at room temperature and pressure....
(Solved)
The empirical formula of a compound is C2H5. When 11.6g of the compound was
allowed to evaporate; it occupied 4.8 dm3 at room temperature and pressure. What is
its molecular formula? (MGV = 24dm3)
Date posted:
May 22, 2019
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Answers (1)
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A sample of unknown gas Z was shown by analysis to contain sulphur and oxygen.
The gas requires 28.3 seconds to diffuse through an aperture into...
(Solved)
A sample of unknown gas Z was shown by analysis to contain sulphur and oxygen.
The gas requires 28.3 seconds to diffuse through an aperture into a vacuum. An
identical amount of oxygen gas passes through the same aperture in 20 seconds.
Determine the molar mass of gas Z. (O=16, S=32).
Date posted:
May 22, 2019
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Answers (1)
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Write equations to show the effect of heat on each of the following.
(a) Sodium hydrogen carbonate.
(b) Silver nitrate
(c ) Sodium nitrate
(Solved)
Write equations to show the effect of heat on each of the following.
(a) Sodium hydrogen carbonate.
(b) Silver nitrate
(c ) Sodium nitrate
Date posted:
May 22, 2019
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Answers (1)
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When small amount of carbon (IV) oxide is passed through lime water, a white
precipitate is formed. When excess carbon (IV) oxide is bubbled through, the...
(Solved)
When small amount of carbon (IV) oxide is passed through lime water, a white
precipitate is formed. When excess carbon (IV) oxide is bubbled through, the white
precipitate dissolves to form a colorless solution.
a) Name the white precipitate.
b) Explain using chemical equations why the white precipitate dissolves in excess of
carbon(IV) oxide.
c) What will happen of the above colorless solution is boiled.
Date posted:
May 22, 2019
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Answers (1)
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When magnesium burns in air, it forms two products. When one of the products
dissolves in water, a colorless gas that turns red litmus paper blue...
(Solved)
When magnesium burns in air, it forms two products. When one of the products
dissolves in water, a colorless gas that turns red litmus paper blue is formed.
a) Name the product that dissolves in water to produce a colorless gas.
b) Write an equation for the formation of the colorless gas.
c) State any one use of the colorless gas.
Date posted:
May 22, 2019
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Answers (1)
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A form four student arranged the apparatus as shown below with the aim of collecting
dry hydrogen gas.
Identify with reasons two mistakes in the above set-up.
(Solved)
A form four student arranged the apparatus as shown below with the aim of collecting
dry hydrogen gas.
Identify with reasons two mistakes in the above set-up.
Date posted:
May 22, 2019
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Answers (1)
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The diagram below shows a Bunsen burner which is used as a source of heat in the
laboratory.
(Solved)
The diagram below shows a Bunsen burner which is used as a source of heat in the
laboratory.
Name the parts labeled: (
A
B
Date posted:
May 22, 2019
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Answers (1)
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Explain why cooking pots made of aluminium do not corrode easily when exposed to
air.
(Solved)
Explain why cooking pots made of aluminium do not corrode easily when exposed to
air.
Date posted:
May 22, 2019
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Answers (1)
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The flow chart below shows the manufacture of a cleansing agent.
(i) Identify each of the substance D and L
(ii) Give one advantage of using this...
(Solved)
The flow chart below shows the manufacture of a cleansing agent.
(i) Identify each of the substance D and L
(ii) Give one advantage of using this cleansing agent over ordinary soap
(iii) What is the effect of the above cleansing agent to the environment.
Date posted:
May 22, 2019
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Answers (1)
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The flow chart below shows some of the stages in the manufacture of sodium carbonate by the
solvay process. Use it to answer the questions that...
(Solved)
The flow chart below shows some of the stages in the manufacture of sodium carbonate by the
solvay process. Use it to answer the questions that follow:
(a) Name substance N
(b) Name the process taking place in
(i) Step II
(ii) Step III
(c) Write an equation for the react producing sodium carbonate.
Date posted:
May 22, 2019
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Answers (1)
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Draw the structure of a sulphur molecule
(Solved)
Draw the structure of a sulphur molecule
Date posted:
May 22, 2019
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Answers (1)
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The following is a list of pH values of some substance:(i) Strong acid (ii)Weak base
(Solved)
The following is a list of pH values of some substance:
Identify:
(i) Strong acid
(ii)Weak base
Date posted:
May 22, 2019
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Answers (1)
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Distinguishing between weak and strong alkali
(Solved)
Distinguishing between weak and strong alkali
Date posted:
May 22, 2019
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Answers (1)
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A dry gas X was passed over heated lead (II) oxide. A grey residue and a gas Y were formed.
The gas Y has no effect...
(Solved)
A dry gas X was passed over heated lead (II) oxide. A grey residue and a gas Y were formed.
The gas Y has no effect on red litmus paper and does not support combustion. Identity:
(i) Gas X
(ii) Gas Y
Date posted:
May 22, 2019
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Answers (1)
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20cm3 of sodium hydroxide solution containing 8.0g/dm3 were required for complete
neutralization of 0.18g of a dibasic acid H2X.
Calculate the relative molecular mass of the acid.
(Solved)
20cm3 of sodium hydroxide solution containing 8.0g/dm3 were required for complete
neutralization of 0.18g of a dibasic acid H2X.
Calculate the relative molecular mass of the acid.
Date posted:
May 22, 2019
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Answers (1)