Question

write the Effective Atomic Number (EAN) Rule ​

Answer 1

Answer:

Generally EAN of central metal ion will be equal to the number of electrons in the nearest noble gas. If the EAN of the central metal is equal to the number of electrons in the nearest noble gas then the complex possess greater stability. EAN= [Z metal – (ox. state of the metal) + 2(coordination number of the metal)].

Answer 2

$\huge\underline{\underline\frak{AnSwEr: -}}$

An early attempt to explain the stability of coordination compounds was made by Sidgwick who proposed an empirical rule known as effective atomic number (EAN) rule. EAN equals total number of electrons around the central metal ion in the complex. EAN rule states that a metal ion continues to accept electrons pairs till it attains the electronic configuration of the next noble gas. Thus if the EAN is equal to 18 (Ar), 36 (Kr), 54 (Xe), or 86 (Rn) then the EAN rule is obeyed.EAN can be calculated with the following. Formula EAN

= number of electrons of metal ion + total number of electrons donated by ligands

= atomic number of metal (Z) - number of electrons lost by metal to form the ion (X)+ number of electrons donated by ligands (Y).

= Z - X + Y