Question

can someone help me? what is the octet rule, with an example?

Answer 1

Octet rule refers to how elements generally prefer to form bonds so as to attain an octet configuration, i.e. have 8 electrons in their valence shell.

For example, chlorine (Cl) is from Group VII and has 7 valence electrons. It will gain one electron (eg from sodium which loses one electron to form Na+) to form Cl-, which has 8 valence electrons and so fulfills the octet rule and is stable. The electronic configuration of sodium is 2.8.1 (if you're in secondary school), or 1s2,2s2,2p6,3s1 (more advanced). So by losing one electron to form Na+, sodium also attains octet configuration.

Hope this clears things up.