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Author Question: A solution is 40.0% by mass benzene (C6H6) in carbon tetrachloride (CCl4) at 20C. The vapor pressure ... (Read 4610 times) |
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."
For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.
Barbituric acid, the base material of barbiturates, was first synthesized in 1863 by Adolph von Bayer. His company later went on to synthesize aspirin for the first time, and Bayer aspirin is still a popular brand today.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
Never take aspirin without food because it is likely to irritate your stomach. Never give aspirin to children under age 12. Overdoses of aspirin have the potential to cause deafness.