Why Does Sugar Melt Ice?

Sugar melts ice

During winter, salt becomes invaluable when dealing with icy roads and walkways. The salt melts the ice and makes traveling safer. Yet it is less well-known that sugar can produce the same result.

Fact

Sugar, and anything else capable of being dissolved in water, will melt ice.

Function

Like salt, sugar melts ice by lowering water's melting and freezing points.

Effects

When sugar is tossed on ice, it dissolves and interferes with the water molecules, which need to bind to ice crystals in order to freeze. Sugar's presence requires the temperature to be much colder before the water molecules come into contact with ice crystals.

Cause

While sugar will melt ice, it still isn't as effective as salt, which breaks down into sodium and chloride ions. In other words, when one molecule of salt dissolves, it adds two components to the solution, providing more interference in preventing water molecules from freezing.

Considerations

Sugar is also more expensive than salt, making it impractical for wide use.

References

• U.S. Department of Energy
• IndianaPublicMedia.org
• ScienceBuddies.org