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Three brands of inks M, N and O were suspected to be contaminated with substance P.
The result is shown below;
i) Which ink was contaminated with...
(Solved)
Three brands of inks M, N and O were suspected to be contaminated with substance P.
The result is shown below;
i) Which ink was contaminated with substance P
ii) Name the ink which was pure
iii) Identify the other ink which was not pure
Date posted:
May 21, 2019
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Answers (1)
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Name three sub – atomic particles found in an atom and state where they are found
(Solved)
Name three sub – atomic particles found in an atom and state where they are found
Date posted:
May 21, 2019
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Answers (1)
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A fixed mass of an ideal gas occupies 200cm3 at a pressure of 740 mmHg.Calculate the volume of the gas at 77-mmHg pressure.
(Solved)
A fixed mass of an ideal gas occupies 200cm3 at a pressure of 740 mmHg.Calculate the volume of the gas at 77-mmHg pressure.
Date posted:
May 21, 2019
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Answers (1)
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Sulphur is soluble in ethanol but not in water while common salt is soluble in water but not in
ethanol
a) Explain why sulphur is soluble in...
(Solved)
Sulphur is soluble in ethanol but not in water while common salt is soluble in water but not in
ethanol
a) Explain why sulphur is soluble in ethanol but hot in water.
b) Explain how a pure sample of sodium chloride can be obtained from a mixture of the two.
Date posted:
May 21, 2019
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Answers (1)
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Explain why potassium is kept under paraffin while phosphorous is kept under water
(Solved)
Explain why potassium is kept under paraffin while phosphorous is kept under water
Date posted:
May 21, 2019
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Answers (1)
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The table below shows the ammeter reading obtained when two different electrolytes of the same concentration were tested.
(Solved)
The table below shows the ammeter reading obtained when two different electrolytes of the same concentration were tested.
Why does ethanoic acid give a lower reading?
Date posted:
May 21, 2019
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Answers (1)
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Study the information in the table below and answer the questions that follow (The letters do not represent the actual symbols of the elements).
(i) What...
(Solved)
Study the information in the table below and answer the questions that follow (The letters do not represent the actual symbols of the elements).
(i) What chemical family do the elements A, B and C belong?
(ii) What is meant by the term ionization energy?
(iii) The 2nd ionization energy is higher that the 1st ionization energy of each. Explain
(Iv) When a piece of element C is placed in cold water, it sinks to the bottom and an
effervescence of a colourless gas that bums explosively is produced. Use a simple diagram to illustrate how this gas can be collected during this experiment.
Date posted:
May 21, 2019
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Answers (1)
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What is the difference between thermosoftening and thermosetting plastics?
(Solved)
What is the difference between thermosoftening and thermosetting plastics?
Date posted:
May 21, 2019
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Answers (1)
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Draw a dot (.) and cross (x) diagram to show bonding in:-
(i) Ammonium ion (NH4)
(ii) Silane (SiH4)
(N=14...
(Solved)
Draw a dot (.) and cross (x) diagram to show bonding in:-
(i) Ammonium ion (NH4)
(ii) Silane (SiH4)
(N=14 H=1 Si=14)
Date posted:
May 21, 2019
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Answers (1)
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A volume of nitrogen gas diffuses through a porous pot in 70 seconds. How long would it take
400cm3 of carbon (iv) oxide to diffuse through...
(Solved)
A volume of nitrogen gas diffuses through a porous pot in 70 seconds. How long would it take
400cm3 of carbon (iv) oxide to diffuse through the same porous pot? (C=12 O=16 N=14)
Date posted:
May 21, 2019
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Answers (1)
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When a few drops of aqueous ammonia were added to copper (ii) chloride solution, a light blue
precipitate was formed. On addition of excess ammonia solution,...
(Solved)
When a few drops of aqueous ammonia were added to copper (ii) chloride solution, a light blue
precipitate was formed. On addition of excess ammonia solution, a deep blue solution was formed.
(a) Identify the substance responsible for the:-
(i) light blue precipitate.
(ii) deep blue solution.
(b) Write an equation for the reaction leading to observation in (a) (ii) above.
Date posted:
May 21, 2019
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Answers (1)
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Pieces of blue and red litmus papers were placed into a beaker containing water into which
Aluminium Chloride had been dissolved.State the observations made on the...
(Solved)
Pieces of blue and red litmus papers were placed into a beaker containing water into which
Aluminium Chloride had been dissolved.State the observations made on the papers. Explain your answer.
Date posted:
May 21, 2019
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Answers (1)
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Is dissolving of aluminium chloride in water a physical or chemical process? Explain
(Solved)
Is dissolving of aluminium chloride in water a physical or chemical process? Explain
Date posted:
May 21, 2019
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Answers (1)
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Explain why graphite conducts electricity while diamond does not.
(Solved)
Explain why graphite conducts electricity while diamond does not.
Date posted:
May 21, 2019
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Answers (1)
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Name the solution and the catalyst used in preparation of oxygen in the laboratory.
(Solved)
Name the solution and the catalyst used in preparation of oxygen in the laboratory.
Date posted:
May 21, 2019
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Answers (1)
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When 31.2g of hydrated. Aluminium oxide ( Al2O3XH2O) was heated to a constant mass of 20.6g of Aluminium oxide ( Al2O3) was obtained. Determine the value...
(Solved)
When 31.2g of hydrated. Aluminium oxide ( Al2O3XH2O) was heated to a constant
mass of 20.6g of Aluminium oxide ( Al2O3) was obtained. Determine the value of x in
hydrated oxide.(Al= 27.0, O=16.0, H=1.0)
Date posted:
May 21, 2019
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Answers (1)
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Aluminium is not used for marine purpose.Give a reason.
(Solved)
Aluminium is not used for marine purpose.Give a reason.
Date posted:
May 21, 2019
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Answers (1)
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Carbon is not used for the reduction of Aluminium oxides.Give a reason
(Solved)
Carbon is not used for the reduction of Aluminium oxides.Give a reason
Date posted:
May 21, 2019
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Answers (1)
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The flow chart below shows industrial extraction Aluminium metal. Study it and answer the questions that follow.
(i) Explain how process T is carried out.
(ii)...
(Solved)
The flow chart below shows industrial extraction Aluminium metal. Study it and answer the questions that follow.
(i) Explain how process T is carried out.
(ii) Name residue P, give a reason.
(iii) Explain why it is necessary to heat Aluminium oxide in presence of cryolite before
electrolysis is carried out.
Date posted:
May 21, 2019
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Answers (1)
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Describe how sulphuric acid is manufactured from sulphur (VI) oxide.
(Solved)
Describe how sulphuric acid is manufactured from sulphur (VI) oxide.
Date posted:
May 21, 2019
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Answers (1)