Question

The separation of a mixture (NH₄Cl, NaCl and SiO₂) is accomplished by: (1) heating the mixture to sublime the NH₄Cl, (2) extracting the NaCl with water, and (3) evaporating water from both the NaCl and SiO₂, to yield the dry mixture.

Could the separation of these three components be accomplished in any other order while using same techniques?
Could the separation of these components be accomplished using other physical methods of separation besides these three?

Could please explain this to me? Thank you in advance!

Answer 1

Q: Could the separation of these three components be accomplished in any other order while using same techniques?

Ans:

In the present exercise the separation order followed is as follows:

1. Sublimation

2. Solubility and Filtration

3. Drying or Evaporation

The separation can also be achieved by another method. Since both NH4Cl and NaCl are soluble in water but not the SiO2. One can first dissolve the mixture in water, filter it and dry the residue (silica) and the filtrate (mixture of NH4Cl and NaCl) separately. After drying the filtrate, the sublimation technique is to be adopted to separate the NH4Cl from the NaCl. Now the separation order will be as follows:

1. Solubility and Filtration

2. Drying or Evaporation

3. Sublimation

Q: Could the separation of these components be accomplished using other physical methods of separation besides these three?

No. Separation of all the components is not feasible by other physical methods, as the both, NH4Cl and NaCl has similar solubility in water. We can achieve separation NH4Cl from the mixture by sublimation only. For separating NaCl from sand, we have to use the solubility procedure only.