chemistry

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Across
  1. 3. Elements in the same group or column have the same number of electrons present in energy levels within the outer shell of the electron cloud
  2. 6. Metals Less reactive, contain more valence electrons in outer energy levels.
  3. 7. is a change of a substance from one form to another without undergoing a change in composition
  4. 8. Metals Contain 2 valence electrons in outer energy levels
  5. 10. If an atom gains electrons it becomes negative and is called
Down
  1. 1. Elements with one valence electron that are very chemically reactive.
  2. 2. is an observable and measurable physical characteristic of matter
  3. 4. If an atom loses electrons it becomes positive and are called
  4. 5. is when one substance combines with another substance to make something completely new with different properties.
  5. 9. are atoms that have a positive or negative charge because they have an unequal number of protons and electrons