$$\text{Percent Yield} = \frac{\text{Actual Yield}}{\text{Theoretical Yield}} \times 100$$

Question 1

Which of the following best describes Avogadro's number and its significance in chemistry?

Accepted Answer

It is the number of particles (atoms, molecules, or ions) in one mole, equal to $$6.022 	imes 10$$^{23}$$.

Question 2

A compound contains 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. What is the empirical formula of the compound?

Accepted Answer

CH$$_2O$

Question 3

Which of the following reactions is a double displacement reaction?

Accepted Answer

$$AgNO_3 + $$NaCl \rightarrow AgCl + $$NaNO_3$$

Question 4

A student dissolves 5.00 g of NaCl in enough water to make 250 mL of solution. What is the molarity of the solution? ($$M_{NaCl} = 58.44 \ g/mol)$$

Accepted Answer

$$0.342 \ M$$

Question 5

Which statement best explains the Law of Conservation of Mass in chemical reactions?

Accepted Answer

The total mass of reactants equals the total mass of products; mass is conserved.

Question 6

Which of the following is the correct balanced chemical equation for the combustion of propane ($$C_3H_8$$)?

Accepted Answer

$$C_3H_8 + 5O_2 \rightarrow 3CO_2 + 4H_2O$$

Question 7

If 2.00 mol of $$H_2$$ reacts with 1.00 mol of $$O_2 to $$form water, what is the limiting reactant?

Accepted Answer

$$O_2$$

Question 8

Which of the following best describes a strong acid?

Accepted Answer

An acid that completely ionizes in water.

Question 9

A solution is prepared by diluting 50.0 mL of 2.00 M $$HCl to a $$final volume of 200.0 mL. What is the final concentration?

Accepted Answer

$$0.50 \ M$$

Question 10

Which of the following is the correct net ionic equation for the reaction between $$NaOH$$ and $$HCl$$?

Accepted Answer

$$OH^- + H^+ \rightarrow H_2O$$

Question 11

Which of the following is a property of a solution described as 'concentrated'?

Accepted Answer

It contains a large amount of solute relative to solvent.

Question 12

Which of the following best describes the Arrhenius definition of an acid?

Accepted Answer

A substance that increases the concentration of $$H^+$$ ions in water.

Question 13

A solution contains 0.10 mol $$Na_2SO_4 in 1.0 L of $$water. What is the concentration of $$SO_4$$^{2-}$$ ions?

Accepted Answer

$$0.10 \ M$$

Question 14

Which of the following is a correct statement about the pH scale?

Accepted Answer

A solution with pH 7 is neutral.

Question 15

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

Accepted Answer

$$	ext{Percent Yield} = \frac{	ext{Actual Yield}}{	ext{Theoretical Yield}} 	imes 100$$

Question 16

Which of the following is a Bronsted-Lowry base?

Accepted Answer

A substance that accepts a proton.

Question 17

A student mixes 100 mL of 0.20 M $$AgNO_3$$ with 100 mL of 0.20 M $$NaCl. $$What mass of $$AgCl ($$molar mass = $$143.32 \ g/mol) $$will precipitate?

Accepted Answer

$$2.87 \ g$$

Question 18

Which of the following is the correct formula for molarity?

Accepted Answer

$$M = \frac{	ext{moles of solute}}{	ext{liters of solution}}$$

Question 19

Which of the following best describes a precipitation reaction?

Accepted Answer

A reaction in which an insoluble solid forms from two aqueous solutions.

Introduction to Chemistry: Key Concepts and Study Guide

Study Guide - Practice Questions