Question

what is the melting point of ice made from distilled water? will the melting point increase or decrease if the ice is made from sea water? give reason

Answer 1

melting point of ice made from distilled water is 0°C.
melting point of any impure liquid is more than pure(original) liquid. hence if the ice is made from sea water( which has impurities) it's melting point will be more.

Answer 2

Melting point of ice which is form from distilled water is 0°C.

If the ice is form from sea water then its melting point decreases because salt lowers the melting point of water. Because the sea water is made of salt ions and water molecules, the salt ions replace some of water molecules. The salt ions which is present in sea water is crack into the ice surface similar like water molecules do, but the salt ions do not become stuck so they end up by slowing down the growth of ice that means the salt block the liquid water molecules from forming ice.