Water can take all three states of matter—solid liquid and gas. All such states are possible because the moving speed of molecules changes. Sometimes a question arises in mind why on adding salt ice starts melting. Actually, when salt is added, water molecules start running fast. So ice starts melting. In simple words, by adding salt freezing point of water gets lowered and so ice melts. Salt is NaCl and on dissolving in water it breaks up into the ions of Na and Cl which, later, prevents ice from forming more too.
However, such effect cannot take place by adding salt if water even in little amount is not present with ice. Ice is coated with a think layer of liquid form of water, so such reaction always takes place.
Not only by adding salt ice can melt but by adding any compound having more ions, it can melt as in the example of calcium chloride.
