A cubic yard of air weighs about 2 pounds at sea level.
31
Cold water weighs more than hot water.
93
The gas that gives rotten eggs their distinctive foul smell may slow ageing and block damaging chemical reactions inside cells, according to scientists in China.
5
Pure water (H2O) does not conduct electricity on its own.
46
Marie Curie, the Nobel prize winning scientist who discovered radium, died of radiation poisoning.
57
The average home creates more pollution than does the average car.
33
If the chemical sodium is dropped into water it will immediately and violently explode.
67
At room temperature, the average air molecule travels at the speed of a rifle bullet.
55