Essay --

Important Discoveries in Chemistry Since the dawn of man, chemistry has been the tool used to fulfill our search for knowledge. A multitude of discoveries have changed the way use chemistry. These discoveries are being made every day and they change the way we see the universe. The following is a sample of important discoveries in chemistry. 1. Discovery of the Atom The idea that atoms make up matter has been around for centuries. However, it has only played a role in chemistry for the past 200 years, and the idea hasn’t taken off until the last 100 years. Ancient Greek philosopher, Demokritos, was one of the first to propose the idea that matter is made up of smaller units. He called these units, â€Å"atoms†. The word atom means unable to be divided. Demokritos also thought that the atoms moved through an infinite â€Å"empty†. Aristotle, however, believed the world contained continuous substances; his belief would be dominant for the time period. The atom would not be scientifically theorized until 1808 by John Dalton. His atomic theory states: All matter contains indivisible and indestructible particles called atoms. The atoms of any one element have the same mass and properties. Compounds are the result of the combination of different atoms. The rearrangement of atoms results in a chemical reaction. Today, nothing in chemistry would be the same without the idea of the atom. Not only is it the basic building block of all matter, but it is also the basic building block of almost all of our knowledge in chemistry. 2. Discovery of the Electron The electron was discovered by J.J. Thompson, a physics professor at Cambridge University. The discovery would be the result of Thompson’s experiments with cathode tubes used in electric and ... ...ial agent was at its greatest. The U.S. pushed industry to produce the penicillin mold. Towards the end of World War II, 650 billion units of penicillin were produced every month. 7. Discovery of Water in Martian Soil A more recent discovery might set the path to discovering life on another planet. Data collected by NASA’s Curiosity rover shows that Martian soil holds about 2% water. The rover’s â€Å"Sample Analysis at Mars† instrument heated a soil sample to 835 degrees Celsius. The resulting gases were oxygen, chlorine, and surprisingly, water vapor. Laurie Leshin of Rensselaer Polytechnic Institute says that a cubic foot of the soil would yield a couple pints of water. From what we know so far, this water is drinkable. However, no one has worked out how to use the soil as a resource for water. One idea is to use a condenser to cool the water vapor into a liquid.