Which of the following sets of operation will completely separate a mixture of sodium chloride, sand and iodine?
addition of water, filtration, evaporation to dryness and sublimation
filtration, evaporation to dryness, addition of water and sublimation
sublimation, filtration, evaporation and addition of water
sublimation, addition of water, filtration and evaporation to dryness
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Since the melting point of sodium chloride is 801 degrees Celsius and iodine sublime's at a temperature which is far less than this it is also very appropriate to carry out sublimation of iodine, then add water to the remaining mixture ,then filter out sand and evaporate the filtrate to dryness to obtain sodium chloride
I completely agree that option (d) is the correct option. Sublimation first before filtration then evaporation to dryness!
i stand to be corrected pls i think the correct answer should be D sublimation first addition of water filtration and then evaporation to dryness
1. . Sublimation of Iodine:
Heat the mixture gently in a fume hood or a well-ventilated area.
Iodine will sublimate (directly transition from solid to gas) and condense on a cooler surface (like an inverted funnel).
Collect the condensed iodine crystals.
The sodium chloride and sand will remain in the original container.
2. Dissolve and Filter:
Add water to the remaining mixture of sodium chloride and sand.
Stir to dissolve the sodium chloride.
Filter the mixture to separate the insoluble sand from the salt solution.
3. Evaporate the Salt Solution:
Heat the salt solution to evaporate the water, leaving behind the solid sodium chloride (salt).
Collect the separated sodium chloride crystals.
Greetings, The Myschool Team.
The correct answer is D (sublimation, addition of water, filtration and evaporation to dryness) and not A(addition of water, filtration, evaporation to dryness and sublimation). As has been rightly noted by my colleagues, iodine sublimes at a temperature lower than the boiling point of water. This thus makes sublimation one of the first things to do. If one goes with A, sublimation occurs after evaporation to dryness which is not true for physical reasons. Therefore, the correct answer is D and not A. Thank you.
