Question

m] Conversion of a solid into a liquid on heating.
8. Potassium chloride is added to water and stirred. A salt solution is obtained which is then
boiled leaving behind a residue
a) Is the above change physical or chemical
b] Name the residue which remains behind after the salt solution is boiled.
c] Is the change reversible or not reversible.
d] Are the composition and properties of the original substance altered.
e] Give a reason why the above experimentation would not be possible, if calcium carbonate
is taken, in place of potassium chloride.​

Answer 1

Answer:

(a) Physical Change

(b) The white residue left behind is potassium chloride.

(c) This change is reversible.

(d) No, the composition and properties of the original substance are not altered.

(e) If we take Calcium carbonate and not KCl, this experiment will not be possible as CaCO_3CaCO

3

is insoluble in water and no new substance with new properties is produced.