What are the n and l quantum numbers for the electrons with the highest energy in each of the following atoms?

Question

a)Sr

b)In

c)Hg

d)Cd

Answer 1

Let's look at the electron configurations for each element.

Sr: [Kr]5s² Highest energy is 5s, so n = 5 and l = 0

In: [Kr]5s²4d¹⁰5p¹ Highest energy is 5p, so n = 5 and l = 1

Hg: [Xe]4f¹⁴5d¹⁰6s² Highest energy is 6s, so n = 6 and l = 0

Cd: [Kr]5s²4d¹⁰ Highest energy is 5s, so n = 5 and l = 0