Properties of materials

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Across
  1. 2. A group of highly reactive nonmetals in the second-to-last column (Group 17) of the periodic table.
  2. 4. The number of protons in the nucleus of an atom. It defines which element an atom is.
  3. 8. Imaginary regions around the nucleus of an atom where electrons are likely to be found. Each shell can hold a maximum number of electrons.
  4. 9. The total number of protons and neutrons in the nucleus of an atom.
  5. 10. A chart that organizes all known elements based on their atomic number and chemical properties.
Down
  1. 1. A group of very unreactive gases in the last column (Group 18) of the periodic table.
  2. 3. A group of highly reactive metals in the first column (Group 1) of the periodic table (excluding hydrogen).
  3. 5. The arrangement of electrons within the different shells and subshells of an atom.
  4. 6. Specific, discrete amounts of energy that electrons in an atom can have. Electrons can only exist at these allowed energy levels.
  5. 7. The forces of attraction or repulsion between charged particles. Opposite charges attract, and like charges repel.