Studying the Rate of Evaporation Using Pocket and Computer-Supported Weighing Scales Available to Purchase

Already when they enter primary school, children have rich everyday experience with factors influencing the rate of liquids’ evaporation. Tea spilled into a large puddle on the table evaporates more rapidly than the same amount remaining in the cup, laundry hanging on a clothesline dries faster on a hot and windy day in comparison with a cold and windless one. We use examples such as these when we tell students that the rate of evaporation is affected by the temperature of a liquid, its surface area, and the airflow above the surface that accelerates the removal of vapors; the type of liquid is also essential. This paper describes a simple way of approximate quantification of these effects in a few hands-on experiments using weighing scales.