a)Haematite
b)crush the ore into powder.
-Add excess dilute nitric (V) acid or sulphuric (VI) acid and warm, filter to obtain
the filtrate. To a portion of the filtrate add aqueous sodium hydroxide or ammonia
solution till in excess ,formation of a green or brown ppt insoluble in excess
reagent indicates Fe2+ or Fe3+,hence the ore contains iron.
Githiari answered the question on September 18, 2017 at 08:25
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Date posted: September 18, 2017. Answers (1)
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Mass of empty evaporating dish = 26.2g
Mass of evaporating dish...(Solved)
In an experiment to determine the solubility in water at 300c, the following results were obtained.
Mass of empty evaporating dish = 26.2g
Mass of evaporating dish + saturated solution = 42.4g.
Mass of evaporating dish + dry solid Y = 30.4g
Use this data to calculate the solubility of Y at 300C.
Date posted: September 18, 2017. Answers (1)
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Date posted: September 18, 2017. Answers (1)
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(a) What is meant by...(Solved)
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(i) State two observations made in the gas jar
(ii) Write an...(Solved)
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(ii) Write an equation for the reaction that took place
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(i) Name the...(Solved)
A student fetched water from a river in a limestone area. He used it for washing and
realized that it did not lather easily.
(i) Name the two ions that prevent lathering
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5.0g of calcium carbonate were allowed to react with 25cm3 of 1.0M hydrochloric acid until
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2X2(g) + Y2(g)<------> 2X2Y(g) H = -197kJ/mol
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H2NCH2COOH + H2NCHCH3COOH ---------->H2O +---------
b)Name the type of polymerization...(Solved)
(a) Proteins are obtained from amino acids monomers. Complete the equation below to show the polymer formed.
H2NCH2COOH + H2NCHCH3COOH ---------->H2O +---------
b)Name the type of polymerization shown above
Date posted: September 18, 2017. Answers (1)
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(a) Write an equation for the reaction
(b) Give one industrial application of the above...(Solved)
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