What makes one atom different from another? There are particles called protons, and they go in the nucleus (the center of an atom). How many protons are in the atom determine what it is. You can’t have half a proton, so they always occur in whole numbers. This number is the whole number on the periodic table box for each element. That’s the atomic number. Sometime I call them “Element 3” or “Element 16,” etc. Those are perfectly good alternative names for lithium and sulfur.

What makes one atom different from another?

There are particles called protons, and they go in the nucleus (the center of an atom).

How many protons are in the atom determine what it is. You can’t have half a proton, so they always occur in whole numbers. This number is the whole number on the periodic table box for each element. That’s the atomic number.

Sometime I call them “Element 3” or “Element 16,” etc. Those are perfectly good alternative names for lithium and sulfur.

Tags: science chemistry protons