Advertisements
Advertisements
Question
How would you confirm that a colourless liquid given to your is pure water ?
Advertisements
Solution
You can boil it and if it starts boiling at 100⁰ C, it might be water. You can also check its reactivity with some metals such as sodium and potassium that react violently with water. The best way, to prove that it is pure water, is to do experiments to see if it has the same capabilities and chemical behaviour as water has.
APPEARS IN
RELATED QUESTIONS
Match the following
| Column A | Column B | ||
| (a) | Molecules | (i) | Water boils |
| (b) | 100° C | (ii) | Evaporation |
| (c) | 0° C | (iii) | Changes from solid to gas |
| (d) | At all temperatures | (iv) | Matter |
| (e) | Camphor | (v) | Water freezes |
The inter-molecular space is maximum in
What is the scientific name of particles which make up mater?
In a beam of sunlight entering a room, we can sometimes see dust particles moving in a haphazard way in the air. Why do these dust particles move?
What are pure substances ? Give two examples of pure substances.
What is the other name for impure substances ? Give two examples of impure substances.
Define a compound. Give two points of evidence to show that sodium chloride is a compound.
State one property in which a solution of sugar in water resembles a mixture of sugar and sand, and one property in which it differs from it.
The element which is not common between the compounds called baking soda and soda ash is
How would you prepare a saturated solution of sodium chloride in water at 25°C ? What will happen if this solution is cooled to 10°C ?
One of the following does not show Tyndall effect. This one is :
Which of the following represents the solubility of sugar in water at 20°C ?
One of the following liquids will leave behind a residue on heating. This one is :
Name the process which can be used to recover salt from an aqueous salt solution.
Name the process which is used in milk dairies to separate cream from milk.
How will you separate a mixture containing sand and sugar ?
How will you separate a mixture of iron filings and powdered carbon ?
A teabag placed in a cup of hot water will diffuse into the water.
______ is used for industrial refrigeration and transporting frozen food.
Define the term matter.
