How to Calculate How Many Protons There Are in Atoms
- 1). Refer to the Periodic Table of Elements. This chart organizes known elements by their atomic number. Hydrogen starts at 1, Lithium is 3, Beryllium is 4, and so on.
- 2). Locate the relevant element. Each element is abbreviated within a small box --- e.g., Nitrogen is labeled as "N." If you are not familiar with these abbreviations, a short search online will find you a Periodic Table that spells out each element fully.
- 3). Notice the number at the top (or top left) of the element box. This is the atomic number. This number is equal to the number of protons there are in one atom of that element. Nitrogen's atomic number is 7, meaning that an atom of nitrogen has 7 protons. If an atom has 8 protons, that changes the element to oxygen. If an atom has 82 protons, it can be identified as lead. Using the Periodic Table will allow you to find the number of protons for any known element.
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