Q: A sample contains 3.0 moles of sodium chloride (NaCl). How many formula units of NaCl are present in the sample?

$1.8 \times 10^{24}$ formula units

Q: Which of the following is the correct formula for calculating percent concentration?

$\text{Percent concentration} = \frac{\text{mass of solute}}{\text{mass of solution}} \times 100$

Question 1

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture in which the composition is uniform throughout

Question 2

Which of the following is the correct formula to convert Celsius temperature to Fahrenheit?

Accepted Answer

$F = \frac{9}{5}C + 32$

Question 3

A sample contains 3.0 moles of sodium chloride (NaCl). How many formula units of NaCl are present in the sample?

Accepted Answer

$1.8 	imes 10^{24}$ formula units

Question 4

Which statement correctly describes the difference between atomic number and mass number?

Accepted Answer

Atomic number is the number of protons; mass number is the sum of protons and neutrons

Question 5

Which of the following is a correct electron configuration for a neutral oxygen atom?

Accepted Answer

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

Question 6

Which of the following compounds is most likely to be soluble in water?

Accepted Answer

NaCl

Question 7

A solution is prepared by dissolving 5.0 g of NaOH in enough water to make 250 mL of solution. What is the molarity of the solution? ($M = \frac{	ext{moles solute}}{	ext{liters solution}}$; molar mass NaOH = 40.0 g/mol)

Accepted Answer

$0.50\ M$

Question 8

Which of the following is a correct balanced chemical equation for the combustion of methane ($CH_4$)?

Accepted Answer

$CH_4 + 2O_2 \rightarrow CO_2 + 2H_2O$

Question 9

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes of an element have the same number of protons but different numbers of neutrons

Question 10

Which of the following is the correct formula for calculating the pH of a solution given $[H_3O^+]$?

Accepted Answer

$pH = -\log[H_3O^+]$

Question 11

Which of the following is a strong acid?

Accepted Answer

HCl

Question 12

Which of the following best describes the lock-and-key model of enzyme activity?

Accepted Answer

The substrate fits exactly into the active site of the enzyme

Question 13

Which of the following is the correct formula for the ideal gas law?

Accepted Answer

$PV = nRT$

Question 14

Which of the following is a correct statement about oxidation and reduction?

Accepted Answer

Oxidation is the loss of electrons; reduction is the gain of electrons

Question 15

Which of the following is the correct structure for a primary alcohol?

Accepted Answer

A carbon atom bonded to one other carbon and an -OH group

Question 16

Which of the following is the correct formula for calculating percent concentration?

Accepted Answer

$	ext{Percent concentration} = \frac{	ext{mass of solute}}{	ext{mass of solution}} 	imes 100$

Question 17

Which of the following is a correct statement about the structure of DNA?

Accepted Answer

DNA consists of two strands forming a double helix

Question 18

Which of the following is the correct formula for calculating the number of moles from mass and molar mass?

Accepted Answer

$	ext{moles} = \frac{	ext{mass}}{	ext{molar mass}}$

Question 19

Which of the following is a correct statement about the effect of temperature on the solubility of a solid in water?

Accepted Answer

Increasing temperature generally increases the solubility of a solid in water

Comprehensive Study Guide: GOB Chemistry Learning Objectives (Chapters 1–11)

Study Guide - Practice Questions

Study Guide - Flashcards