Hot water can freeze faster than cold water.
181
The bark of an older redwood tree is fireproof.
65
Iron weighs more after it rusts.
68
The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
51
If you are locked in a completely sealed room, you will die of carbon dioxide poisoning first before you will die of oxygen deprivation.
117
Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
At room temperature, the average air molecule travels at the speed of a rifle bullet.
55
Some toothpastes and deodorants contain the same chemicals found in antifreeze.
38