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(i) Ammonia – method C
Reason – ammonia is less dense than air and therefore collected by upward delivery.
(ii) Carbon dioxide – method A
Reason – CO2 is dense than air and therefore collected by downward delivery.
(iii) Oxygen – method B – It is slightly soluble in water so it can be collected over water method conveniently.
Kavungya answered the question on March 25, 2019 at 08:39
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(i) Oily and greasy –
(ii) Blood stains –
(iii) Perspiration stains –
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(a) Coloured extracts of grass dissolved in ethanol.
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iii) On the diagram label the cathode.
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