Iron weighs more after it rusts.
16
During photosynthesis, plants emit light humans can’t see, but NASA can see that light from space - and they've even made maps of it!
21
Cold water weighs more than hot water.
93
The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
At room temperature, the average air molecule travels at the speed of a rifle bullet.
55
The bark of an older redwood tree is fireproof.
65
In 1999, Harvard physicist Lene Hau was able to slow down light to 17 meters per second and in 2001, was able to stop light completely.
39
The only letter not appearing on the Periodic Table is the letter "J".
180