Chemical Symbols & Classification

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  1. 4. The scientist who introduced the modern system of representing chemical elements using letters as symbols.
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  1. 1. The total number of atoms present in a single molecule of an element.
  2. 2. A letter or pair of letters used to represent a single atom of a chemical element.
  3. 3. A positively charged particle found inside the nucleus of an atom whose count determines the atomic number.
  4. 5. A negatively charged particle that orbits outside the atom's nucleus.