Electron Configuration and Quantum Numbers

This video tutorial covers solving multiple-choice problems related to quantum numbers, including calculating the maximum number of electrons in energy levels, identifying sublevels, and understanding electron configurations. It explains the correspondence between quantum numbers and sublevels, highlights exceptions like chromium's electron configuration, and discusses paramagnetic elements. The tutorial also explores the maximum number of electrons with specific quantum numbers and provides examples of electron configurations in both ground and excited states.

What is the maximum number of electrons that can be found in the n=3 energy level?

• 14

• 10

• 18

• 8

Which sublevel corresponds to the quantum numbers n=3 and l=2?

• 3s

• 3f

• 3d

• 3p

Which of the following sublevels does not exist?

• 2p

• 3d

• 2d

• 5f

How many unpaired electrons does an atom of chromium contain?

• 5

• 3

• 4

• 6

How many paired electrons are in an atom of chlorine?

• 16

• 14

• 15

• 17

Which element is paramagnetic?

• Neon

• Magnesium

• Phosphorus

• Calcium

What is the maximum number of electrons with the quantum numbers n=4 and ms=+1/2?

• 16

• 32

• 8

• 24

How many orbitals are located in the n=4 energy level?

• 8

• 16

• 24

• 32

Which electron configuration represents an element in the excited state?

• 1s2 2s2 2p4

• 1s2 2s1 2p3

• 1s2 2s2 2p6 3s1

• 1s2 2s2 2p6

Which group of elements corresponds to the configuration ns2 np4?

• Halogens

• Chalcogens

• Alkaline earth metals

• Alkali metals