In zero gravity, a candle's flame is round and blue.
16
A coal power station puts 100 times more radiation into the air than a nuclear power plant producing the same amount of energy.
7
Forensic scientists can determine a person's sex, age, and race by examining a single strand of hair.
101
Brass doorknobs automatically disinfect themselves in about 8 hours.
18
The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
51
Hot water can freeze faster than cold water.
181
Cellophane is not made of plastic. It is made from a plant fiber, cellulose, which has been shredded and aged.
44