Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
Pumice is the only rock that floats on water.
14
In zero gravity, a candle's flame is round and blue.
16
The bark of an older redwood tree is fireproof.
65
MIT has developed a camera that captures the speed of light at a trillion frames per second.
20
Cold water weighs more than hot water.
93
The smell of freshly cut grass is actually a plant distress call.
31
Kissing actually has the biological purpose of passing on biological information and chemical signals to assess mating possibilities and status.
9