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Salt is often used to melt ice on roads during the winter because it lowers the freezing/melting point of water. When salt dissolves in water, individual Na and Cl- ions break away from the salt lattice and become surrounded by water molecules. Why would this cause ice to melt

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Answer:

See explanation

Step-by-step explanation:

The addition of an impurity lowers the melting point of a solid. If we add salt to ice, the melting point of the ice is lowered.

As this salty water is in contact with the ice, more of the salt dissolves to yield Na^+ and Cl^- and leads to the melting of more ice.

Freezing point is a colligative property hence it is affected by the presence of impurities. Hence, the addition of NaCl causes ice to melt faster.

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