Q: Which of the following statements about effective nuclear charge ($$Z_{\text{eff}}) is $$correct?

$$Z_{\text{eff}}$$ increases as you move across a period from left to right.

Question 1

Which of the following best explains why the atomic radius increases as you move down a group in the periodic table?

Accepted Answer

Additional principal energy levels are added, increasing the distance of valence electrons from the nucleus.

Question 2

Which element would you expect to have the highest first ionization energy based on periodic trends?

Accepted Answer

Neon (Ne)

Question 3

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

Accepted Answer

$$[\mathrm{Ar}]\ 4s^2$\ 3d^6$

Question 4

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

Accepted Answer

$$Z_{	ext{eff}}$$ increases as you move across a period from left to right.

Question 5

Which of the following ions is isoelectronic with argon ($$\mathrm{Ar}$$)?

Accepted Answer

$$\mathrm{Cl}^-$$

Question 6

Which of the following best describes Hund’s Rule?

Accepted Answer

Electrons occupy degenerate orbitals singly with parallel spins before pairing.

Question 7

Which of the following elements is expected to be the most metallic?

Accepted Answer

Antimony (Sb)

Question 8

Which of the following ions is expected to be paramagnetic?

Accepted Answer

$$\mathrm{Fe}^{3+}$$

Question 9

Which of the following statements about the periodic law is correct?

Accepted Answer

When elements are arranged in order of increasing atomic number, certain sets of properties recur periodically.

Question 10

Which of the following best explains why the first ionization energy generally increases across a period?

Accepted Answer

The effective nuclear charge increases, holding valence electrons more tightly.

Question 11

Which of the following elements would have the electron configuration $$[\mathrm{Ar}]\ 4s^2$\ 3d$$^{10}$$\ 4p^4$?

Accepted Answer

Selenium (Se)

Question 12

Which of the following is a correct statement about the size of ions compared to their parent atoms?

Accepted Answer

Cations are smaller and anions are larger than their parent atoms.

Question 13

Which of the following elements is expected to have the most negative electron affinity?

Accepted Answer

Chlorine (Cl)

Question 14

Which of the following best describes the Pauli Exclusion Principle?

Accepted Answer

No two electrons in an atom can have the same set of four quantum numbers.

Question 15

Which of the following elements would you expect to have the largest atomic radius?

Accepted Answer

Rubidium (Rb)

Question 16

Which of the following is the correct order of filling for atomic orbitals according to the aufbau principle?

Accepted Answer

$$1s \rightarrow 2s \rightarrow 2p \rightarrow 3s \rightarrow 3p \rightarrow 4s \rightarrow 3d$$

Question 17

Which of the following best explains why the electron configuration of chromium (Cr) is $$[\mathrm{Ar}]\ 4s^1$\ 3d^5$ instead of $$[\mathrm{Ar}]\ $$4s^2$$\ $$3d^4$$?

Accepted Answer

A half-filled d sublevel is especially stable due to exchange energy.

Question 18

Which of the following statements about metallic character is correct?

Accepted Answer

Metallic character increases down a group and decreases across a period.

Question 19

Which of the following best describes the trend in electron affinity across a period for main-group elements?

Accepted Answer

Electron affinity becomes more negative (more exothermic) from left to right.

Question 20

Which of the following best explains why halogens tend to form 1− anions?

Accepted Answer

They have one fewer electron than the next noble gas and gain one electron to achieve a stable configuration.

Chapter 3: Periodic Properties of the Elements – Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards