Crystallisation
Trending Questions
(a) Why is crystallisation technique better than evaporation technique?
(b) Write any two physical properties of each metals and nonmetals.
Name a method to separate copper sulphate from water
How will you prepare a saturated solution of sodium chloride in water at ? What will happen if this solution is cooled?
A good method to separate alum from impure samples is:
Filtration
Sedimentation
Crystallization
Sublimation
Impure salts can be purified by the process :
Fractional evaporation
Distillation
Fractional purification
Crystallization
Can matter undergo chemical changes on heating?
Why a hot saturated solution should be cooled slowly, followed by slow evaporation of the solution during crystallisation?
How can I make Alum at Home?
Arrange the following process in the correct order of obtaining pure salt crystals from impure salt.
A. Crystallization of Salt
B. Preparing saturated solution
C. Heating saturated solution
Both Sarika and Mohan were asked to make a salt solution. Sarika was given a teaspoonful of salt and half a glass of water, whereas Mohan was given twenty teaspoons full of salt and half a glass of water. 1) How would they make salt solutions?.2) Who would be able to prepare a saturated solution?
Give an activity to show that more salt can be added to a saturated solution on heating.
When a solution is said to be saturated?
(a) How would they make salt solutions?
(b) Who would be able to prepare saturated solution?
Explain how will you determine the solubility of NaNO3 at room temperature.
One of the most common solvents used for crystallization is
Water
Chlorine
NItrogen
Alcohol
(II) It is a temporary change.
(III) The new substances formed have properties different from those of the reacting substances.
- I, III
- I, II
- II, III
- All of the above
Explain a method to separate common salt from a mixture of chalk powder and common salt.
Which of the following is separated by crystallisation?
Soil in water
Sugar syrup
Lemon juice
Starch in water
22 When a hot saturated solution is heated, crystals will be formed. Is it correct? If no, correct the statement.
Impure compounds of copper sulphate or salt from sea water can be purified using the method called:
Filteration
Vapourisation
Crystallisation
Solidification
(b) Both Sarika and Mohan were asked to make salt solution. Sarika was given a teaspoonful of salt and half a glass of water, whereas Mohan was given twenty teaspoons full of salt and half a glass of water. Who would be able to prepare saturated solution? [1 mark]
(c) Lemonade is prepared by mixing lemon juice and sugar in water. You wish to add ice to cool it. Should you add ice to the lemonade before or after dissolving sugar ? In which case would it be possible to dissolve more sugar? [3 marks]
- Milk at room temperature
- Hot boiling milk
- Lukewarm milk
- Ice-cold milk
(a) One of the components changes directly from solid to gaseous state.
(b) Two or more coloured constituents soluble in some solvent.
- filtration
- distillation
- evaporation
- sublimation
A sublimate component is obtained by the process of ____________.
evaporation
sublimation
boiling
centrifugation
- Crystallization
- Sublimation
- Chromatography
- Distillation