Iron weighs more after it rusts.
16
One ragweed plant can release as many as one billion grains of pollen!
51
Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
Each day is longer than the previous on by 0.00000002 seconds which is 13 seconds each century!
116
The bark of an older redwood tree is fireproof.
65
Nylon is made from coal and petroleum.
42
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