Lowering The Freezing Point Of Water Using Salt

Purpose

To demonstrate that the freezing point of water can be reduced by putting ice in a salt water bath.
 

Equipment

Beaker with icewater, salt (NaCl), digital thermometer.

 

Setup Time

5 min.
 

    Images

    i4-35

    Description

    The temperature of an ice and water mixture is measured with a digital thermometer. Adding salt to the icewater mixture reduces its temperature. The thermometer can be used to stir the mixture. By this technique the freezing point can be lowered as much as 15 degrees celcius.