Each year, southern California has about 10,000 earthquakes. Most of them are so small that they aren't even felt. Only several hundred are greater than magnitude 3.0, and only about 15-20 are greater than magnitude 4.0.

Gastric acid is one of the main secretions of the stomach. It consists mainly of hydrochloric acid and acidifies the stomach content to a pH of 1 to 2.

Urushiol oil is what causes the painful rash in most people who touch poison ivy. Only one-billionth of a gram of urushiol oil is needed to cause a rash!

Lemons and limes have particularly high concentrations of citric acid.

The largest recorded earthquake in the world was a magnitude 9.5 quake in Chile on May 22, 1960.

Nobelium, a synthetic chemical element with symbol No and atomic number 102, is named in honor of Alfred Nobel, the inventor of dynamite who bequeathed his fortune to institute the Nobel Prizes.

For his scientific work, Pauling was awarded the Nobel Prize in Chemistry in 1954.

Although Michael Faraday received little formal education, he was one of the most influential scientists in history. His main discoveries include the principles underlying electromagnetic induction, diamagnetism and electrolysis.

George Washington Carver was an American botanist and inventor. His reputation is largely based on his promotion of alternative crops to cotton, such as peanuts and sweet potatoes.

She named the first chemical element that she discovered polonium after her native country--Poland.