Iron weighs more after it rusts.
68
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
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
Indoor pollution is 10 times more toxic than outdoor pollution.
62
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
Neanderthal man had a brain capacity 100cc larger than modern man's.
50
Aluminum used to be more valuable than gold!
84