Answer:
Chemical elements are categorized in the Periodic Table based on the number of protons and electrons. The electrons are the sub-atomic particle, which revolves around the atomic nucleus and has a negative charge. The protons are the positive charged sub-atomic particles, which are present in the nucleus of the atom.
Explanation:
The chemical element is a pure particle, which is made up of atoms. The atoms in a neutral chemical element have the same number of electrons and protons. In the case given above, calcium has fewer protons and electrons than rubidium. Calcium has the atomic number 20, such that it belongs to group 2 and period 4. The number of electrons and protons in calcium (no net charge) is 20. Similarly, the rubidium belongs to group 1 and period 5. The element has the atomic number 37, such that the number of electrons and protons in rubidium is 37.
