A student observes that an egg sinks in pure water but floats after a large amount of common salt is dissolved in the same water.
(i) Explain qualitatively how dissolving salt changes the density of water.
(ii) Using the concept of relative densities, account for the different behaviours of the egg in pure and salt water.
(iii) Describe what will happen to the egg if more salt is added until the density of the solution becomes exactly equal to the density of the egg.