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Explain why galvanized iron objects are better protected even when scratched.
(Solved)
Explain why galvanized iron objects are better protected even when scratched.
Date posted:
May 20, 2019
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Answers (1)
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Painting, oiling, galvanizing or tin-plating are methods of preventing rusting.Explain how these methods are similar in the way they prevent rusting.
(Solved)
Painting, oiling, galvanizing or tin-plating are methods of preventing rusting.Explain how these methods are similar in the way they prevent rusting.
Date posted:
May 20, 2019
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Answers (1)
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The following set up was used to react steam with Iron Powder.
(a) The water was heated before heating the iron powder. Explain why this was...
(Solved)
The following set up was used to react steam with Iron Powder.

(a) The water was heated before heating the iron powder. Explain why this was necessary.
(b) Write an equation for the reaction that took place between steam and iron powder
(c) State how gas L would be collected without using water.
Date posted:
May 20, 2019
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Answers (1)
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25cm3 of 0.1m sulphuric (VI) acid required 20cm3 of sodium carbonate solution for complete neutralization. Calculate the concentration of sodium carbonate in moles per litre.
(Solved)
25cm3 of 0.1m sulphuric (VI) acid required 20cm3 of sodium carbonate solution for complete neutralization. Calculate the concentration of sodium carbonate in moles per litre.
Date posted:
May 20, 2019
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Answers (1)
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Using dots (•) and cross (x) show the bonding in hydroxonium ion
(Solved)
Using dots (•) and cross (x) show the bonding in hydroxonium ion
Date posted:
May 20, 2019
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Answers (1)
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A compound W react with chlorine to form another compound Y whose structural
formula is as follows:
(i) Give the name and structural formula of Compound W...
(Solved)
A compound W react with chlorine to form another compound Y whose structural
formula is as follows:

(i) Give the name and structural formula of Compound W
(ii) What type of reaction leads to the formation of compound Y from compound W.
Date posted:
May 20, 2019
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Answers (1)
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Draw the structure of the following compounds:
(i) 2 – Methyprop-1-ene
(ii) Hexan – 2- ol
(Solved)
Draw the structure of the following compounds:
(i) 2 – Methyprop-1-ene
(ii) Hexan – 2- ol
Date posted:
May 20, 2019
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Answers (1)
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A mixture contains sodium chloride, ammonium chloride, and silver chloride. Explain how
you can obtain pure samples of each salt.
(Solved)
A mixture contains sodium chloride, ammonium chloride, and silver chloride. Explain how
you can obtain pure samples of each salt.
Date posted:
May 20, 2019
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Answers (1)
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State and explain the observations made when sodium metal is put into a boiling tube containing propan–l-ol
(Solved)
State and explain the observations made when sodium metal is put into a boiling tube containing propan–l-ol
Date posted:
May 20, 2019
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Answers (1)
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Raw rubber is heated with sulphur in the manufacture of natural rubber.
(Solved)
Raw rubber is heated with sulphur in the manufacture of natural rubber.
(i) What name is given to the process?
(ii Why is the process necessary.
Date posted:
May 20, 2019
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Answers (1)
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Below is a flow chart. Study it and answer the questions that follow (i) Name the process in step I (ii) Name compound R Reagent Y....
(Solved)
Below is a flow chart. Study it and answer the questions that follow: -

(i) Name the process in step I
(ii) Name compound R
Reagent Y
(iii) Write equation for the reaction in step II
(c) Explain why 0.1 M hydrochloric acid has a pH of 1 while 0.1M ethanoic acid has a pH of 3
Date posted:
May 20, 2019
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Answers (1)
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Calculate the volume of hydrogen gas produced at s.t.p when 1.15g of sodium metal
react with water. (Na=23, molar gas volume=22400cm3)
(Solved)
Calculate the volume of hydrogen gas produced at s.t.p when 1.15g of sodium metal
react with water. (Na=23, molar gas volume=22400cm3)
Date posted:
May 20, 2019
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Answers (1)
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What is the function of calcium chloride during extraction of sodium metal?
(Solved)
What is the function of calcium chloride during extraction of sodium metal?
Date posted:
May 20, 2019
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Answers (1)
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In an experiment to electroplate a copper spoon with silver, a current of 0.5A was passed for 18 minutes. Calculate the amount of silver deposited...
(Solved)
In an experiment to electroplate a copper spoon with silver, a current of 0.5A was passed for 18 minutes. Calculate the amount of silver deposited on the spoon ( IF =96500 coulombs,Ag=108)
Date posted:
May 20, 2019
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Answers (1)
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Study the diagram below and answer the questions that follow. When some hydrogen chloride gas is allowed into water....
(Solved)
Study the diagram below and answer the questions that follow.

When some hydrogen chloride gas is allowed into water and the mixture stirred, the bulb lights and gasses X and Y are formed.
(a) Name
(i) Gas X
(ii) Gas Y
(b) Explain why the bulb does not light before the chloride gas is let into the water
Date posted:
May 20, 2019
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Answers (1)
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The structure of ammonium ion is shown below. Name the type of bond represented in the diagram by N-----> H
(Solved)
The structure of ammonium ion is shown below

Name the type of bond represented in the diagram by N-----> H
Date posted:
May 20, 2019
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Answers (1)
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Give a reason why ammonia gas is highly soluble in water.
(Solved)
Give a reason why ammonia gas is highly soluble in water.
Date posted:
May 20, 2019
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Answers (1)
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A mass of 56g a saturated solution of salt X at 250C yield 14g of the solid when
evaporated to dryness. What is the solubility of...
(Solved)
A mass of 56g a saturated solution of salt X at 250C yield 14g of the solid when
evaporated to dryness. What is the solubility of the salt at 250C.
Date posted:
May 20, 2019
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Answers (1)
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The extraction of aluminium from its ore takes place in two stages, purification stage
and electrolysis stage. The diagram below shows the set up for the...
(Solved)
The extraction of aluminium from its ore takes place in two stages, purification stage
and electrolysis stage. The diagram below shows the set up for the electrolysis stage.

(a) Name the ore from which aluminium is extracted.
(b) Name one impurity which is removed at purification stage.
(c) Label on the diagram each of the following:
Anode
Cathode
Region containing the electrolyte
(d) The melting point of aluminium oxide is 20540C but electrolysis is done between 8000C -
9000C.
(i) Why is the electrolysis not carried out at 20540C.?
(ii) What is done to lower the temperature of the electrolysis cell to 8000C - 9000C?
(iii) The aluminium which is produced is tapped off as liquid. What does this imply
about its melting point?
(e) A typical electrolysis cell uses a current of 40000 ampheres. Calculate the mass (in kilograms) of aluminium produced in one hour.
Date posted:
May 20, 2019
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Answers (1)
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The flow chart below outlines some of the process involved during extraction of copper.
(Solved)
The flow chart below outlines some of the process involved during extraction of copper.

a) (i) Write the formula of copper pyrite.
(ii) Name liquid T
(iii) Write equations for the reactions taking place in the 2nd roasting furnace.
(iv) Identify substance B and write equation for the reaction that take place in the smelting furnace.
(v) State the purpose of substance F.
Date posted:
May 20, 2019
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Answers (1)