what is octect rule
Answers
Answer:
The octet rule is a chemical rule of thumb that reflects the observation that main group elements tend to bond in such a way that each atom has eight electrons in its valence shell, giving it the same electronic configuration as a noble gas.
According to octet rule, atom tends to have 8 electrons in the valence shell to attain stable configuration.
Significance: It explains the reason behind the chemical combination of different atoms to form ionic or covalent bond.
Limitations :
(1) Hydrogen with 1 electron attains stability by sharing, gaining or losing 1 valence electron. It does not need to complete octet to attain stability. Also, He has only 2 electrons and is stable.
(2) Incomplete octet: In certain molecules such as BeH
2
, BeCl
2
, BH
3
, BF
3
, the central atom has less than 8 electrons