Question

Your friend is having trouble writing the electron configuration for Nickel Ni. In your own words describe how you would teach your friend how to write an electron configuration, and then write the configuration for Ni.

Answer 1

My friend should begin with the basics by knowing the order of the configuration such as 1s^2, 2s^2, 2p^6, 3s^2, 3p^6, 4s^2, 3d^10, 4p^6, 5s^2, 4d^10, and so on.

I would ask my friend to find the atomic number of Nickel or Ni which is 28 on the periodic table.

I would note that the "exponents" should equal to the atomic number of the element.

Like so:

1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8.

Answer 2

Answer: The electronic configuration of nickel is $1s^22s^22p^63s^23p^64s^23d^8$

Explanation: To write the electronic configuration, first count the total number of electrons in an element.

Total number of electrons in an element = Atomic number of that element.

Atomic number of Nickel = 28

So, number of electrons = 28

For filling of electrons, we follow some rules:

Rule 1. The orbitals with lowest energy will be filled first. Order of filling electrons in the orbitals follow the pattern 1s, 2s, 2p, 3s, 3p, 4s, 3d, etc.

Rule 2. In an orbital, only electrons are permitted and they must have opposite spin. This rule basically means that no two electrons can have all the 4 quantum numbers same. This rule was known as Pauli Exclusion Principle.

Rule 3. The electrons are singly filled first in each orbital having same spin, then only pairing occurs. This rule was known as Hund's Rule.

Filling up of electrons of Nickel follows:

$Ni(Z=28)=1s^22s^22p^63s^23p^64s^s3d^8$