Question 1

Which quantum number primarily determines the energy level of an electron in a hydrogen atom?

Accepted Answer

The principal quantum number $$n$$

Question 2

What is the maximum number of electrons that can occupy a single orbital?

Accepted Answer

Two

Question 3

Which set of quantum numbers is NOT allowed for an electron in an atom?

Accepted Answer

$$n=2,\ l=2,\ m_l=0,\ m_s=+\frac{1}{2}$$

Question 4

How many different orientations are possible for a $$d$$ orbital?

Accepted Answer

Five

Question 5

Which statement best describes the shape of a $$p$$ orbital?

Accepted Answer

Two lobes with a nodal plane between them

Question 6

For a $$3p$$ orbital, what are the possible values of the magnetic quantum number $$m_l$$?

Accepted Answer

$$-1, 0, +1$$

Question 7

Which rule states that electrons fill degenerate orbitals singly before pairing up?

Accepted Answer

Hund's Rule

Question 8

What is the condensed electron configuration for sodium ($$Z=11$$)?

Accepted Answer

$$[Ne]3s^1$

Question 9

How many unpaired electrons are present in the ground-state electron configuration of oxygen ($$Z=8$$)?

Accepted Answer

Two

Question 10

Which quantum number is responsible for the orientation of an orbital in space?

Accepted Answer

Magnetic quantum number $$m_l$$

Question 11

What is the total number of orbitals in the $$n=3$$ shell?

Accepted Answer

Nine

Question 12

Which of the following best explains why the $$4s$$ orbital is filled before the $$3d$$ orbital?

Accepted Answer

The $$4s$$ orbital has a lower energy than the $$3d$$ orbital

Question 13

Which quantum number can have values of $$+\frac{1}{2} or$$ $$-\frac{1}{2}$$?

Accepted Answer

Spin quantum number $$m_s$$

Question 14

How many nodal planes are present in a $$2p$$ orbital?

Accepted Answer

One

Question 15

Which statement is true about the electron configuration of elements in the same group of the periodic table?

Accepted Answer

They have the same number of valence electrons

Question 16

If an atom has the electron configuration $$1s^2$$ $$2s^2$$ $$2p^6$$ $$3s^2$$ $$3p^4$$, how many valence electrons does it have?

Accepted Answer

Four

Question 17

Which principle states that no two electrons in an atom can have the same set of four quantum numbers?

Accepted Answer

Pauli Exclusion Principle

Question 18

What is the electron configuration for a neutral carbon atom ($$Z=6$$)?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^2$$

Question 19

Which orbital type has the greatest number of nodal planes?

Accepted Answer

$$f$$ orbital

Question 20

In a hospital MRI machine, the magnetic field interacts with the spin of electrons. Which quantum number is directly related to this property?

Accepted Answer

Spin quantum number $$m_s$$

Quantum Numbers and Atomic Orbitals: Study Notes for General Chemistry

Study Guide - Practice Questions