Question 1

Which of the following best explains why the 4s orbital fills before the 3d orbital in multielectron atoms?

Accepted Answer

Because the 4s orbital has a lower energy than the 3d orbital due to penetration and shielding effects.

Question 2

According to Coulomb’s law, what happens to the potential energy of two oppositely charged particles as they get closer together?

Accepted Answer

Their potential energy decreases.

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

Which element has the following ground-state electron configuration: $$[Ne]3s^2$ 3p^4$?

Accepted Answer

Sulfur (S)

Question 5

A main-group element has an outer electron configuration of $$ns^2$$ $$np^4. $$What charge is likely for an ion of this element?

Accepted Answer

$$2^-$$

Question 6

Which of the following statements about atomic radius is correct?

Accepted Answer

Atomic radius decreases from left to right across a period.

Question 7

Which of the following ions is isoelectronic with neon ($$Ne$$)?

Accepted Answer

$$F^-$$

Question 8

Which of the following best describes Hund’s rule?

Accepted Answer

Electrons occupy degenerate orbitals singly before pairing.

Question 9

Which of the following elements is expected to have the highest first ionization energy?

Accepted Answer

Argon (Ar)

Question 10

Which of the following statements about the effective nuclear charge ($$Z_{eff}) is $$true?

Accepted Answer

$$Z_{eff}$$ increases as you move across a period.

Question 11

Which of the following best explains why cations are smaller than their parent atoms?

Accepted Answer

Cations lose electrons, resulting in a higher effective nuclear charge on the remaining electrons.

Question 12

Which of the following elements is most likely to form an anion with a $$2^-$$ charge?

Accepted Answer

Oxygen (O)

Question 13

Which of the following electron configurations represents a transition metal in its ground state?

Accepted Answer

$$[Ar]4s^1$ 3d^5$

Question 14

Which of the following best describes the trend in metallic character across a period in the periodic table?

Accepted Answer

Metallic character decreases from left to right.

Question 15

Which of the following statements about electron affinity is correct?

Accepted Answer

Electron affinity becomes more negative as you move to the right across a period.

Question 16

A neutral atom of which element has the following orbital diagram? 
$$\uparrow\downarrow (1s$$), $$\uparrow\downarrow (2s$$), $$\uparrow\downarrow (2p$$), $$\uparrow\downarrow (2p$$), $$\uparrow\downarrow (2p)$$

Accepted Answer

Neon (Ne)

Question 17

Which of the following best describes the difference between the van der Waals radius and the covalent radius?

Accepted Answer

The van der Waals radius is measured between two nonbonded atoms, while the covalent radius is measured between two bonded atoms.

Question 18

Which of the following is the correct electron configuration for the $$Al^{3+}$$ ion?

Accepted Answer

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

Question 19

Which of the following best explains why the first ionization energy decreases as you move down a group?

Accepted Answer

The outermost electrons are farther from the nucleus and are less tightly held.

Chapter 9: Periodic Properties of the Elements – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards