Question 1

Which of the following electron configurations represents a neutral atom of sulfur (S)?

Accepted Answer

$1s^2\ 2s^2\ 2p^6\ 3s^2\ 3p^4$

Question 2

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

Accepted Answer

Chlorine (Cl)

Question 3

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

Accepted Answer

$Na^+$

Question 4

Which of the following statements best explains why atomic radius decreases across a period from left to right?

Accepted Answer

The nuclear charge increases, pulling electrons closer.

Question 5

Which of the following elements is paramagnetic?

Accepted Answer

Oxygen ($O$)

Question 6

Which of the following pairs of elements would you expect to form an ionic compound?

Accepted Answer

Sodium and Chlorine

Question 7

Which of the following molecules has a Lewis structure with a double bond?

Accepted Answer

$CO_2$

Question 8

What is the correct name for the compound $Na_2SO_4$?

Accepted Answer

Sodium sulfate

Question 9

Calculate the molar mass of calcium chloride ($CaCl_2$).

Accepted Answer

$111.0\ g/mol$

Question 10

A sample contains $0.50$ moles of $H_2O$. What is the mass of the sample?

Accepted Answer

$9.0\ g$

Question 11

Which of the following formulas represents a binary molecular compound?

Accepted Answer

$CO_2$

Question 12

How many molecules are present in $36.0\ g$ of water ($H_2O$)? ($M_{H_2O} = 18.0\ g/mol$)

Accepted Answer

$1.20 	imes 10^{24}$

Question 13

What is the empirical formula of a compound containing $40.0\%$ carbon, $6.7\%$ hydrogen, and $53.3\%$ oxygen by mass?

Accepted Answer

$CH_2O$

Question 14

A compound has an empirical formula of $CH_2$ and a molar mass of $56\ g/mol$. What is its molecular formula?

Accepted Answer

$C_4H_8$

Question 15

Which of the following best describes the trend in ionization energy as you move down a group in the periodic table?

Accepted Answer

Ionization energy decreases.

Question 16

If $24.0\ g$ of $Na_2SO_4$ is dissolved in water, how many moles of $Na_2SO_4$ are present? ($M_{Na_2SO_4} = 142.0\ g/mol$)

Accepted Answer

$0.17$ moles

Question 17

Which of the following is the correct Lewis structure for $NH_3$?

Accepted Answer

Nitrogen with three single bonds to hydrogen and one lone pair

Question 18

A compound contains $27.3\%$ carbon, $72.7\%$ oxygen by mass. What is its empirical formula?

Accepted Answer

$CO_2$

Question 19

Which of the following best explains why fluorine has a higher electronegativity than lithium?

Accepted Answer

Fluorine has a higher nuclear charge and smaller atomic radius.

Question 20

How many grams of oxygen are present in $50.0\ g$ of $H_2O$? ($M_{H_2O} = 18.0\ g/mol$)

Accepted Answer

$27.8\ g$

General Chemistry Study Guide: Atomic Structure, Periodic Table, and Chemical Compounds

Study Guide - Practice Questions