The Periodic Table is a well-organized chart that contains all 118 known elements in the universe. These elements are the ...

Electrons in atoms occupy energy levels, also called electron shells, outside the nucleus. Different shells can hold different maximum numbers of electrons. The electrons in an atom occupy the ...

In this activity, students will use the online periodic table, ptable.com, to investigate a number of chemistry concepts. Students will use this online resource to explore information about the ...

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.

The periodic table is a way of arranging elements according ... and the period that each element belongs to represents the number of electron shells that the atom has. TULELA: So for example ...