Chemistry

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Across
  1. 2. the proton is a positive electric charge.
  2. 4. a stable subatomic particle with a charge of negative electricity.
  3. 5. Electron: a valence electron is an outer shell electron that is associated with an atom.
  4. 6. Chemistry is the scientific discipline involved with elements.
  5. 8. Levels: Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found.
  6. 9. the basic unit of a chemical element.
Down
  1. 1. a subatomic particle of about the same mass as a proton but without an electric charge.
  2. 3. the central part of an atom that comprises nearly all of the atomic mass and that consists of protons and neutrons.
  3. 6. reaction: a process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in physical form or a nuclear reaction.
  4. 7. Cloud: An electron cloud is ​the region of negative charge surrounding an atomic nucleus that is associated with an atomic orbital.