To figure this out the element with the electron config of we first count the electrons. Those are the small number placed at the top after the letters.

For this element we have 2 + 2 + 1 = 5. That gives us a total of 5 electrons. In a neutral atom, electrons will equal the number of protons.

In a neutral atom, electrons will equal the number of protons. On the periodic table we can usually find the atomic number above the element symbol. This is the same as the number of protons. In a neutral atom electrons = protons.

Since we had 5 electrons, we therefore have 5 protons, and the element with atomic number 5. We look up 5 on the periodic table and it is Boron (B).

Sometimes we have ions, these aren’t neutral, they have a charge. You can tell bc there will be a + or – sign in the superscript after the element symbol.

Neutral Elements: for example Na, Fe, N, O, H. All the elements as listed on the Periodic Table are neutral. Ions: for example Na+, Fe 3+, N 3-, O 2-, H+ .
Ions are elements that have lost or gained electrons.

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