Iron weighs more after it rusts.
16
Approximately 70 percent of the earth is covered by water. Only 1 percent of this water is drinkable.
65
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
One 75-watt bulb gives more light than three 25-watt bulbs.
57
Scientists have developed a microparticle filled with oxygen that can be injected into the blood stream, enabling us to live without breathing.
21
The bark of an older redwood tree is fireproof.
65
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310