The first shell can hold up to 2 electrons, the second shell can hold up to 8 (2 + 6) electrons, the third shell can hold up to 18 (2 + 6 + 10) and so on.
It really base on facts ,hypotheses,evidences,concepts,
You can identify a substance, by testing the melting and boiling point and find a known substance that has the same melting and boiling points as the one tested
<span>Rule of the octet is used in chemistry to indicate the tendencies of the atoms when they complete the energy level to obtain stability. Covalent bonds are what occurs when two atoms join and reach the stable octet. They are related because through this union electrons are shared and the covalent bond is produced and the rule of the octet is given to show the tendency of this union.</span>