CHEM 1A Lecture Notes - Lecture 1: Henri Becquerel, Atomic Number, Magnesium
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Matter- any particular thing that has mass and can take up space. Chemists focus on studying matter to know more about the world around us and the changes we undergo. They also study the interrelationship between matter and energy. Atoms are the building blocks of matter. Matter that are visible to our eyes= macroscopic scale. Matter at the atomic level= microscopic scale. The word atomos (atoms) came from greek philosophers and means. Radioactivity- particles that are emitted from unstable atoms; first founded by. Alpha- largest wave out of the three, positively charged, moves slowly, weakest. Beta- negatively charged, moves fast but not as fast as gamma. Gamma- electromagnetic waves that has high frequency and moves the fastest (at the speed of light), strongest and most dangerous. The mass of a proton is 1. 673x10-27. The mass of an neutron is 1. 675x10-27. The mass of an electron is 9. 11x10-31. An element is determined by the amount of protons it has.
