Question 1

Which statement best describes the difference between atoms of different elements?

Accepted Answer

Atoms of different elements have different numbers of protons.

Question 2

A neutral atom of sodium has an atomic number of 11 and a mass number of 23. How many neutrons does it contain?

Accepted Answer

12

Question 3

Which of the following is the correct electron configuration for a neutral atom of oxygen (atomic number 8)?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^4$$

Question 4

Which group on the periodic table contains elements that are all colorless, nonreactive gases at room temperature?

Accepted Answer

Group 18 (noble gases)

Question 5

What is the charge and approximate mass (in amu) of a neutron?

Accepted Answer

Charge: 0, Mass: 1 amu

Question 6

Which of the following best explains why the noble gases are chemically unreactive?

Accepted Answer

Their outermost electron shell is completely filled.

Question 7

An isotope of carbon has a mass number of 14. What is its symbol using isotope notation?

Accepted Answer

$$^{14}_{6}C$$

Question 8

Which of the following statements about atomic structure is correct?

Accepted Answer

Most of the mass of an atom is concentrated in the nucleus.

Question 9

Which element is most likely to have similar chemical properties to sodium?

Accepted Answer

Potassium

Question 10

What is the trend in atomic radius as you move from left to right across a period in the periodic table?

Accepted Answer

Atomic radius decreases.

Question 11

Which of the following electron configurations represents a noble gas?

Accepted Answer

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

Question 12

Which of the following is true about isotopes?

Accepted Answer

Isotopes have the same number of protons but different numbers of neutrons.

Question 13

Which subshell contains orbitals that are dumbbell-shaped?

Accepted Answer

p subshell

Question 14

How many electrons can the third shell of an atom hold?

Accepted Answer

18

Question 15

Which rule states that electrons occupy the lowest energy orbitals available first?

Accepted Answer

Aufbau principle

Question 16

A neutral atom of chlorine has 17 electrons. How many valence electrons does it have?

Accepted Answer

7

Question 17

Which of the following elements is an alkaline earth metal?

Accepted Answer

Magnesium

Question 18

What is the electron configuration for a neutral atom of neon (atomic number 10)?

Accepted Answer

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

Question 19

Which of the following best describes valence electrons?

Accepted Answer

Electrons in the outermost shell of an atom.

Question 20

Which of the following elements is a halogen?

Accepted Answer

Bromine

Chap 2 Atoms, Atomic Structure, and the Periodic Table: Foundations of Modern Atomic Theory

Study Guide - Practice Questions