Question 1

Which quantum number determines the shape of an atomic orbital?

Accepted Answer

The angular momentum quantum number $l$

Question 2

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

Accepted Answer

Two

Question 3

Which of the following sets of quantum numbers is NOT allowed for an electron in an atom?

Accepted Answer

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

Question 4

Which orbital is spherical in shape?

Accepted Answer

s orbital

Question 5

How many possible values of $m_l$ are there for a $d$ orbital?

Accepted Answer

5

Question 6

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

Accepted Answer

Pauli Exclusion Principle

Question 7

What is the electron configuration for the fluoride ion ($F^-$)?

Accepted Answer

$1s^2\ 2s^2\ 2p^6$

Question 8

Which element has the electron configuration $[Ar]\ 4s^2\ 3d^5$?

Accepted Answer

Manganese

Question 9

Why does the atomic radius generally decrease across a period from left to right?

Accepted Answer

Because the nuclear charge increases, pulling electrons closer

Question 10

Which of the following ions is largest in an isoelectronic series containing $O^{2-}$, $F^-$, $Na^+$, and $Mg^{2+}$?

Accepted Answer

$O^{2-}$

Question 11

What is the general trend for first ionization energy ($I_1$) across a period?

Accepted Answer

It increases

Question 12

Which of the following best explains why anions are larger than their parent atoms?

Accepted Answer

Anions have more electrons, increasing electron-electron repulsion

Question 13

Which element is expected to have the highest first ionization energy?

Accepted Answer

Neon

Question 14

What is the condensed electron configuration for potassium ($K$), atomic number 19?

Accepted Answer

$[Ar]\ 4s^1$

Question 15

Which of the following statements about Hund's Rule is correct?

Accepted Answer

Electrons in degenerate orbitals maximize the number of unpaired electrons with parallel spins

Question 16

Which orbital type is being filled for the lanthanide elements?

Accepted Answer

4f

Question 17

A transition metal ion $Fe^{2+}$ loses electrons from which orbital(s) first?

Accepted Answer

4s

Question 18

Which of the following elements is a main-group element?

Accepted Answer

Oxygen

Question 19

Which of the following electron configurations represents a ground state atom?

Accepted Answer

$1s^2\ 2s^2\ 2p^6\ 3s^2\ 3p^6\ 4s^2\ 3d^6$

Question 20

Which of the following best describes the electron affinity of chlorine?

Accepted Answer

It is negative and exothermic

Electronic Structure of Atoms: Quantum Numbers, Orbitals, and Electron Configurations

Study Guide - Practice Questions