Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
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
Iron weighs more after it rusts.
68
If the chemical sodium is dropped into water it will immediately and violently explode.
67
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
It takes a photon 170,000 years to travel from the core of the Sun to the surface, but only 8 minutes to travel the rest of the way to Earth.
6
Approximately 70 percent of the earth is covered by water. Only 1 percent of this water is drinkable.
65