Question

how does salt melt ice? (based on nature of chemical bonds and properties of water)

Answer 1

salt tends to attract water. salt is made of a metal and a non metal losely bond in a ionic binding. because of the water being a dipolar molecule it can stick to the ions in the salt and dissolve those.
so if you mix salt and ice, you make a connection between the ions in the salt and the dipolar water molecules in the ice. the water sticks to the ions in the salt creating an ionic binding. the water molecule prefers sticking to the ion than to other water molecules (benefit in energy). so it takes heat energy from the surrounding air to break its binding to other water molecules. that causes a decreasing temperature around it (salt-ice mixtures where used in former times to cool thing eg making icecreame, i made the experience of getting down to -18°C with such a mixture)
so, the salt attracts the water, and the water then dissolves the salt. and you gain a salty water and a cooling effect to the surrounding

Answer 2

Simple answer: salt lowers the melting point of water

Answer 3

yeah that is basically the resulting effect ;)