The ice cubes in the punch melted much faster. This is because of heat. Heat is actually a measure of matter's molecular motion. In ice, molecules move slowly. In air, molecules move faster. In steam, the molecules are moving so fast that they can escape into the air.

Heat can move around by radiation, conduction and convection. In our ice cube experiment, the heat moved very slowly from the air into the ice cubes. The ice cubes in the punch melted faster because the heat moved more rapidly from the water by both convection and conduction.
Newton once gave a party for fifty youngsters. He wanted to serve iced punch to all his guests. To save time, Newton decided to have the punch glasses poured BEFORE the party.

He worried about the ice melting too soon and the punch becoming too warm. He couldn't decide what to do so he tried an experiment.

He filled up one glass with BOTH the ice cubes and the punch.

He filled another glass with ONLY ice cubes so he could add the punch later.

Which ice cubes do you predict will last longer?

Scroll down to see the answer.

Reprinted with the permission from Ed Schevick Science Action Labs.
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