(a) (i) Liebig condenser
(ii) It helps in determining the boiling range so that pure ethanol is obtained. When liquids boil, there temperatures remain constant.
(iii) Point C;
Explanation: The cold water will provide maximum contact with the distillate in the delivery tube.
(iv) Part A: Fractionating column.
-It increases the surface area for condensation of the substance whose boiling point has not been reached.
-Provides a surface in which vapour condenses into liquid and the liquid redistills.
(v) -Ethanol was collected first
-It has a lower boiling point 780C, hence it boils first.
(vi) Fractional distillation
(vii) Have different but close boiling points.
(viii) -Manufacture of spirits
-Fractional distillation of crude oil.
-Obtaining oxygen from liquid air.
(b) (i) Add to any unhydrous cobalt chloride paper which turn from blue to pink.
OR: Add the liquid to anhydrous copper (II) sulphate which turns from white to blue.
(ii) By determining the boiling point of the liquid.
maurice.mutuku answered the question on September 3, 2019 at 10:46
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