Question

the total number of orbitals in an energy level designated by principal quantum number n is equal to
1.n
2.2n2
3.2n
4.n2

Answer 1

it's n^2 option 4 is correct

Answer 2

Answer:

Total number of orbitals in an energy level for principal quantum number 'n' is equal to n².

Therefore, the option (4) is correct.

Explanation:

Principle quantum number is designated by 'n'. It indicates the principle shell of an atom. It described the most probable distance of an electron from the nucleus.

• Larger the value of the 'n' means the electron is present at the greater distance from the nucleus. This implies the larger atomic size of an atom.
• The value of principle quantum number is positive integer. The value n=1 indicates the innermost as well as the lowest  energy level. The value of n = 1, 2, 3, 4,........
• The total number of orbitals in an energy level or shell is equal to square of principle quantum number. For the principle quantum number 'n', the number of orbital will be equal to  n².
• For example, for n=1, only one orbital which is 1s-orbital. For n=2 , the number of orbitals = (2)² = 4, which are 2s, $2p_{x},\; 2p_{y},\; and\;\; 2p_{z}$.