Define octet rule. Write its significance and limitations.
Answers
Answer:
firstly octet mean 8 so according to this rule the outer most shell of electron only carry 8 electron
Explanation:
One limitation of the octet rule is that it cannot be applied to the nonmetals after silicon in the Periodic Table. These elements can “expand their octet” and have more than eight valence electrons around the central atom. Molecules with an odd number of electrons such as NO and NO2 cannot satisfy the octet rule
Significance of octate rule: The octet rule successfully explains the formation of chemical bonds depending upon the nature of the element. It is used to determine stability in atoms. The octet rule helps to figure out how atoms will bond with one another.
Answer:
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 BeH2 , BeCl2 , BH3 , BF3 , the central atom has less than 8 electrons in its valence shell, yet the molecule is stable.
(3) Expanded octet: In certain molecules such as PF5 , SF6 , IF7 , H2SO4 , the central atom has more than 8 valence electrons, yet the molecule is stable.