Question 1

Which quantum number determines the overall size and energy of an atomic orbital?

Accepted Answer

Principal quantum number, $$n$$

Question 2

What is the maximum number of $$d$$ orbitals that can exist for a given principal quantum number $$n$$?

Accepted Answer

Five

Question 3

Which statement best describes the Pauli Exclusion Principle?

Accepted Answer

No two electrons in the same atom can have identical sets of quantum numbers.

Question 4

For a $$2p$$ orbital, what are the possible values of the magnetic quantum number $$m_l$$?

Accepted Answer

$$-1, 0, 1$$

Question 5

Which orbital type is characterized by being spherical in shape and having $$l = 0$$?

Accepted Answer

$$s$$ orbital

Question 6

How many radial nodes are present in a $$3s$$ orbital?

Accepted Answer

2

Question 7

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

Accepted Answer

Magnetic quantum number, $$m_l$$

Question 8

What is the electron configuration for the element oxygen ($$Z = 8$$)?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^4$$

Question 9

Which of the following best describes the meaning of the wave function $$\psi in $$quantum mechanics?

Accepted Answer

It describes the probability density of finding an electron in a particular region of space.

Question 10

A $$3d$$ orbital has which value for the angular momentum quantum number $$l$$?

Accepted Answer

$$l = 2$$

Question 11

Which of the following electron configurations violates the Pauli Exclusion Principle?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^7$$

Question 12

Which quantum number can have only two possible values, $$+\frac{1}{2}$$ and $$-\frac{1}{2}$$?

Accepted Answer

Spin quantum number, $$m_s$$

Question 13

If an atom has electrons in the $$2p$$ orbitals, how many electrons can occupy all $$2p$$ orbitals in total?

Accepted Answer

6

Question 14

Which of the following statements about $$p$$ orbitals is correct?

Accepted Answer

They have two lobes and one angular node.

Question 15

In a multi-electron atom, which type of orbital is most effective at shielding outer electrons from the nucleus?

Accepted Answer

$$s$$ orbitals

Question 16

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 17

Which of the following elements has the electron configuration $$1s^2$$ $$2s^2$$ $$2p^6$$ $$3s^2$$?

Accepted Answer

Magnesium ($$Z = 12)$$

Question 18

Which quantum number is associated with the shape of the orbital?

Accepted Answer

Angular momentum quantum number, $$l$$

Question 19

A hospital uses sodium vapor lamps for lighting. Which electron transition in sodium is responsible for the characteristic yellow emission?

Accepted Answer

Transition from $$3p to$$ $$3s$$

Question 20

Which of the following best explains why $$s$$ orbitals are more effective at shielding than $$d$$ orbitals in multi-electron atoms?

Accepted Answer

$$s$$ orbitals penetrate closer to the nucleus due to their spherical shape.

Electronic Structure of Atoms: Quantum Mechanics and Atomic Orbitals

Study Guide - Practice Questions