Sound travels about 4 times faster in water than in air.
408
Research indicates that plants grow healthier when they are stroked.
173
Iron weighs more after it rusts.
68
For every gallon of sea water, you get more than a quarter pound of salt.
45
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
Brass doorknobs automatically disinfect themselves in about 8 hours.
18
A ball of glass will bounce higher than a ball made of rubber.
73
German chemists made a replica of a trophy the size of one molecule.
68