1.1.11

Atomic Number

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Atomic Number and Mass Number

The atomic number is the number of protons in the atom. The mass number of an atom (or relative mass) is calculated by adding the number of protons and neutrons found in a nucleus. These numbers can be found for each element in the periodic table.

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Sodium

  • Mass number (top) = 23.
  • Atomic number (bottom) = 11.
Illustrative background for CarbonIllustrative background for Carbon ?? "content

Carbon

  • Mass number (top) = 12.
  • Atomic number (bottom) = 6.

Jump to other topics

1Atomic Structure

2Chemical Bonding

3Quantitative Chemistry

4Chemical Changes

5Energy Changes

6The Rate & Extent of Chemical Change

7Organic Chemistry

8Chemical Analysis

9Chemistry of the Atmosphere

10Using Resources

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