When room-temperature washers are placed in hot water, the temperature of the washers increases and the temperature of the water decreases. Energy from the water is transferred to the washers. When ...

Matter is made up of very small parts called atoms. Atoms can combine in different numbers and in different ways to make different molecules. Atoms and molecules make up all of the different ...

The ancient Greek and Indian philosophers who first conjectured that matter was made of tiny little bits of stuff would not believe that now, more than 25 centuries later, we can actually see them.