a) What method can be used to separate a mixture of ethanol and propanol?
(b) (i) Explain how a solid mixture of sulphur and sodium chloride can be separated into solid sulphur and solid sodium chloride.
(ii) How can one determine if the solid sulphur is pure?
(c) The table below gives the solubilities of potassium bromide and potassium sulphate at #0^0C# and #40^0C#
When an aqueous mixture containing 60g of potassium bromide and 7g
of potassium sulphate in 100g of water at #80^0C# was cooled to #0^0C#, some crystals were formed.
(i) Identify the crystals.
(ii) Determine the mass of the crystals formed
(iii) Name the method used to obtain the crystals.
(iv) Suggest one industrial application of the method named in (c)(iii) above.
Answer:
a)Fractional Distillation
b)i)Add water to the mixture; sodium chloride being an ionic compound dissolves. Filter the mixture to remove sulphur as a residue. Evaporate the filtrate to obtain. Sodium chloride.
ii)Check its melting point. It should have a sharp melting point
c)(i)Potassium Bromide
ii)60-55=5g
iii)Fractional Crystallization
iv)Used in the separation of ammonium chloride and sodium hydrogen carbonate in the solvay process
b)i)Add water to the mixture; sodium chloride being an ionic compound dissolves. Filter the mixture to remove sulphur as a residue. Evaporate the filtrate to obtain. Sodium chloride.
ii)Check its melting point. It should have a sharp melting point
c)(i)Potassium Bromide
ii)60-55=5g
iii)Fractional Crystallization
iv)Used in the separation of ammonium chloride and sodium hydrogen carbonate in the solvay process
Share To Friends Via:
in an experiment, soap solution was added to three separate samples of water. The table below shows the volumes of the soap solutions required to form lather with #1000cm^3# of each sample of water before and after boiling.
a) Which water sample is likely to be soft? Explain.
(b) Name the cause of change in the volume of soap solution used in sample III 
