Cellophane is not made of plastic. It is made from a plant fiber, cellulose, which has been shredded and aged.
44
Iron weighs more after it rusts.
16
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
Hot water can freeze faster than cold water.
181
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
Sound travels about 4 times faster in water than in air.
408
Each day, up to 150 species of life become extinct.
-23