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
Iron weighs more after it rusts.
16
Some toothpastes and deodorants contain the same chemicals found in antifreeze.
38
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
51
Only 12,000 years ago there was a species closely related to modern humans called Homo floresiensis that had been living on an Indonesian Island. They used fire and rather advanced tools, yet were only about 3 feet tall and weighed around 25kg.
15
If the chemical sodium is dropped into water it will immediately and violently explode.
67