Question 1

Which of the following best describes the concept of periodicity in the periodic table?

Accepted Answer

The repetitive pattern of a property for elements based on atomic number.

Question 2

Which trend correctly describes how effective nuclear charge ($$Z_{\mathrm{eff}}) $$changes across a period from left to right?

Accepted Answer

$$Z_{\mathrm{eff}}$$ increases because the number of protons increases while shielding remains relatively constant.

Question 3

Which of the following ions is largest in size?

Accepted Answer

$$\mathrm{Cl}^{-}$$

Question 4

Why are cations generally smaller than their parent atoms?

Accepted Answer

Cations lose outermost valence electrons, reducing electron-electron repulsion and shrinking the electron cloud.

Question 5

Which element has the highest ionization energy among the following: $$\mathrm{Ca}$$, $$\mathrm{Ba}$$, $$\mathrm{O}$$, $$\mathrm{Se}$$?

Accepted Answer

$$\mathrm{O}$$

Question 6

What is the correct order of atomic radius from smallest to largest for the following: $$\mathrm{S}$$, $$\mathrm{Cs}$$, $$\mathrm{Cl}$$?

Accepted Answer

$$\mathrm{Cl} \u003c \mathrm{S} \u003c \mathrm{Cs}$$

Question 7

Which of the following statements about electron affinity is correct?

Accepted Answer

Electron affinity is the energy change accompanying the addition of an electron to a gaseous atom.

Question 8

Fluorine is the most electronegative element because:

Accepted Answer

It has the highest effective nuclear charge and is one electron short of a full octet.

Question 9

Which of the following best explains why noble gases have very low electron affinity?

Accepted Answer

They have a full valence shell and do not want to gain electrons.

Question 10

A hospital uses sodium ($$\mathrm{Na}) $$and potassium ($$\mathrm{K}) $$ions in IV fluids. Which ion is larger and why?

Accepted Answer

$$\mathrm{K}^{+} is $$larger because it is lower in the group and has more electron shells.

Question 11

Which of the following elements has the lowest electronegativity?

Accepted Answer

$$\mathrm{Ba}$$

Question 12

If you compare the first and second ionization energies of magnesium ($$\mathrm{Mg}$$), which is true?

Accepted Answer

The second ionization energy is higher because it removes an electron from a more stable configuration.

Question 13

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

Accepted Answer

Anions have more electrons, increasing electron-electron repulsion and expanding the electron cloud.

Question 14

Which element would you expect to have the highest electron affinity: $$\mathrm{C}$$, $$\mathrm{Sn}$$, $$\mathrm{Zn}$$, $$\mathrm{K}$$?

Accepted Answer

$$\mathrm{C}$$

Question 15

A chemist is comparing the reactivity of alkali metals. Which property explains why cesium ($$\mathrm{Cs}) $$reacts more vigorously with water than sodium ($$\mathrm{Na}$$)?

Accepted Answer

Cesium has a lower ionization energy, making it easier to lose its valence electron.

Question 16

Which of the following statements about trends in atomic size is correct?

Accepted Answer

Atomic size increases down a group and decreases across a period from left to right.

Question 17

Which of the following elements would have the lowest effective nuclear charge ($$Z_{\mathrm{eff}}$$)?

Accepted Answer

$$\mathrm{Rb}$$

Question 18

Which of the following best describes the relationship between electron affinity and stability of the resulting ion?

Accepted Answer

The more energy released (more negative electron affinity), the more stable the ion.

Question 19

Which of the following elements is most likely to form a cation?

Accepted Answer

$$\mathrm{Na}$$

Chapter 7: Periodic Properties of the Elements – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards