Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
At room temperature, the average air molecule travels at the speed of a rifle bullet.
55
A cubic yard of air weighs about 2 pounds at sea level.
31
Columbia University has developed an artificial tree that passively soaks up carbon dioxide from the air using "leaves" that are 1,000 times more efficient than true leaves that use photosynthesis.
15
Iron weighs more after it rusts.
68
Sound at the right vibration can bore holes through a solid object.
134