Question 1

Which statement best describes the periodic law as established by Mendeleev and Meyer?

Accepted Answer

Elements are arranged in order of increasing atomic mass, and certain properties recur periodically.

Question 2

Which of the following is the correct electron configuration for aluminum (Al)?

Accepted Answer

$$1s^22s^22$p^63s^23$p^1$$

Question 3

Which element's $$4^+$$ ion would have the electron configuration $$[Kr]4d$$^{10}$$?

Accepted Answer

Sn

Question 4

What is the ground state electron configuration for molybdenum (Mo)?

Accepted Answer

$$[Kr]5s^14$d^5$

Question 5

Which of the following ions or atoms has the smallest radius?

Accepted Answer

Be$$^{2+}$$

Question 6

Arrange the following species in order of increasing atomic or ionic radius: Br, Br$$^-$$, Cl, Se$$^{2-}.$$

Accepted Answer

Cl \u003c Br \u003c Br$$^-$$ \u003c Se$$^{2-}$$

Question 7

Which of the following best explains why atomic radius decreases across a period?

Accepted Answer

Effective nuclear charge ($$Z_{eff}) $$increases, pulling electrons closer to the nucleus.

Question 8

What is the approximate effective nuclear charge ($$Z_{eff}) $$experienced by a 3p electron in phosphorus (P)? Use $$Z_{eff} = Z - S$$ and Slater's rules.

Accepted Answer

$$Z_{eff} \approx 5$$

Question 9

Which of the following is the full electron configuration for zirconium (Zr, $$Z=40$$)?

Accepted Answer

$$1s^22s^22$p^63s^23$p^64s^23$d^{10}4p^65$s^24d^2$

Question 10

Which of the following elements has the highest first ionization energy?

Accepted Answer

Ne

Question 11

Why do cations generally have smaller radii than their parent atoms?

Accepted Answer

Loss of electrons reduces electron-electron repulsion and may result in loss of an entire energy level.

Question 12

Which of the following is the electron configuration of germanium (Ge, $$Z=32$$)?

Accepted Answer

$$[Ar]4s^23$d^{10}4p^2$

Question 13

Which region of the periodic table corresponds to the group of elements in which the 5d orbitals are being filled?

Accepted Answer

The third row of the d-block (transition metals, period 6)

Question 14

Which of the following best describes the trend in atomic radius for main group elements as you move down a group?

Accepted Answer

Atomic radius increases due to addition of energy levels.

Question 15

Which of the following is a correct statement about the electron configuration of transition metals?

Accepted Answer

The principal quantum number of the d orbital being filled is equal to the row number minus one.

Question 16

Which of the following explains the exception to the trend in first ionization energy between nitrogen and oxygen?

Accepted Answer

Pairing of electrons in oxygen's 2p orbital increases electron-electron repulsion, lowering its ionization energy.

Question 17

Which of the following elements is most likely to form a noble gas configuration by losing one electron?

Accepted Answer

Na

Question 18

Which of the following best describes the trend in first ionization energy as you move from left to right across a period?

Accepted Answer

Ionization energy increases due to increasing effective nuclear charge.

Chapter 8: Periodic Properties of the Elements – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards