- Add water to the solid mixture.
- V dissolves while W will not.
- Filter to obtain W as residue.
- Heat the filtrate to evaporate the water.
sharon kalunda answered the question on March 27, 2019 at 12:54
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(a) Write the equation for the reaction taking place in region A.
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Date posted: March 27, 2019. Answers (1)
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Suggest two ways of increasing the yield of X2Y.
Date posted: March 27, 2019. Answers (1)
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Date posted: March 27, 2019. Answers (1)
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(i) Equation;
(ii) Name:
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(a) Name solid P
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(a) (i) State and explain the observation at the anode when the switch is switched on.
(ii) What precaution should be taken when carrying out this experiment?
(iii) Write the equation of the reaction taking place at the Anode.
(iv) Why are graphite electrodes used in the experiment?
(v) On the diagram, indicate the direction of flow of electrons.
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(b) State the difference in conduction of electric current between Molten Lead (II) Bromide and Lead Metal.
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Date posted: March 27, 2019. Answers (1)
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Describe how nitrogen is obtained from air on a large scale.
(a) (i) Name one source of hydrogen gas used as a raw material in the above process.
(ii) Name chamber A.
(iii) Write an equation for the reaction taking place in the catalytic chamber.
(iv) In the Haber process optimum temperature of 5000C and 200 atmospheres of pressure are used to get optimum yield of
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(b) Give two reasons why finely divided iron is the commonly used catalyst.
(c) State and explain the observation made when dry ammonia gas is passed over heated copper (II) Oxide
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Date posted: March 27, 2019. Answers (1)
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(i) Name the process taking place in step (I).
(ii) Describe chemical test that can be carried out to show the identity of organic compound A.
(iii) Give the name of the following:
I. A:
II. B:
(iv) Give the structural formulae of substance C.
(v) Name the type of reaction that occurs in:
I. Step IV
II. Step VI:
(vi) Give the reagent and the condition necessary for step VI.
Reagent:
Condition:
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I. CH2CHCHCH2CH3
II. CH C C H3
Date posted: March 27, 2019. Answers (1)
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(b) Identify the athletes that tested positive for the illegal steroids.
Date posted: March 27, 2019. Answers (1)
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(a) What is meant by a double salt?
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(i) Trona
(ii) Basic magnesium carbonate.
Date posted: March 27, 2019. Answers (1)
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Nitrogen...(Solved)
Using dots (•) and crosses (x) to represent electrons, show bonding in the compound formed when the following elements reacts. (N = 14, H = 1).
Nitrogen and Hydrogen.
Date posted: March 27, 2019. Answers (1)