Periodic Table

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Across
  1. 2. A substance that cannot be separated or broken down into simpler substances
  2. 3. An arrangement of the elements in order of their atomic numbers such that elements with similar properties fall in the same column,or group.
  3. 4. A charged particlae thar forms when an atom or group of atoms gain or loses one or more electrons
  4. 6. A characteristic of a substance that does not involve a chemical change
  5. 8. The sum of the numbers of protons and neutrons in the nucleus of an atom.
Down
  1. 1. A region around the nucleus of an atom where electrons are likely to be found.
  2. 5. The number of the protons in the nucleus of an atom.
  3. 7. A one-,two-,or three-letter abbreviation of the name of an element.