The picture shows a close-up of one carbon atom. A hydrogen atom has one proton as the nucleus and one electron in the region outside the nucleus. The electron and proton are attracted to each other.

These are almost one-quarter of the periodic table and are mainly found in the first four periods. Of these, 11 are essential elements that our bodies need in larger amounts: oxygen, carbon ...

The periodic table can be divided into metals and non ... The carbon dioxide molecules each have one black carbon atom and two red oxygen atoms (CO₂). It’s a mixture. There are three ...