B) How would you separate the following?
i. Different pigments of flower petals. [ process name only ]
ii. Potassium nitrate and potassium chloride. [ process name only]
iii. Iodine + Ammonium chloride + Sand [show flow chart only]
Answers
Answer:
a) Sodium chloride from its solution in water Evaporation.
(b) Ammonium chloride from a mixture containing sodium chloride and ammonium chloride Sublimation.
(c) Small pieces of metal in the engine oil of a car Filtration
(d) Different pigments from an extract of flower Chromatography.
(e) Butter from curd Centrifugation.
(f) Oil from water Using separating funnel
(g) Tea leaves from tea Filtration
(h) Iron pins from sand Magnetic Separation
(i) Wheat grains from husk Winnowing
(j) Fine mud particles suspended in water Centrifugation.
Answer:
(i) The pigments from an extract of flower petal can be separated out by the process of chromatography.
____________________________________________
(ii) Heating & Cooling: The mixture is heated to get a saturated solution and it crystallises on cooling. Now since, potassium nitrate is more soluble it gets filtered out from the hot saturated solution and recrystallised in hot water and then dried. This separates the two mixtures into crystals.
_____________________________________________
(iii)
Mixture: Sand, ammonium chloride and (elemental) iodine.
Extract the iodine as a purple solution with chloroform.
2) Stir well the remaining mixture in a pot of distilled water, then let the mixture set. Collect the floating sawdust from the surface.
3) Filter out the sand with a paper filter, then rinse two to three times with distilled water. All ammonium chloride will be in the aqueous solution. Boil off the water to get it dry.
4) Dry the sand which has remained in the paper filter.
Explanation: