Q: Which of the following is the correct formula for calculating molarity ($$M$$)?

$$M = \dfrac{\text{moles of solute}}{\text{volume of solution in liters}}$$

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

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

Q: Which of the following equations is used to relate the rate of effusion of two gases to their molar masses?

$$\dfrac{\text{Rate}_1}{\text{Rate}_2} = \sqrt{\dfrac{M_2$}{M_1$}}$$

Q: Which of the following is the correct formula for calculating the total pressure of a mixture of gases?

$$P_{\text{total}} = P_1$ + P_2$ + P_3$ + \ldots$$

Question 1

Which of the following best describes a spectator ion in a chemical reaction?

Accepted Answer

An ion that is present in the reaction mixture but does not participate in the chemical change.

Question 2

A student mixes 50.0 mL of 0.200 M NaCl with 50.0 mL of 0.200 M AgNO$$_3. $$What mass of AgCl (molar mass = 143.32 g/mol) will precipitate? (Assume complete reaction.)

Accepted Answer

$$0.716\ 	ext{g}$$

Question 3

Which of the following statements about strong and weak acids is correct?

Accepted Answer

Strong acids ionize completely in water, while weak acids ionize only partially.

Question 4

Which of the following is the correct formula for calculating molarity ($$M$$)?

Accepted Answer

$$M = \dfrac{	ext{moles of solute}}{	ext{volume of solution in liters}}$$

Question 5

A 25.0 mL sample of HCl is titrated with 0.100 M NaOH. If it takes 30.0 mL of NaOH to reach the endpoint, what is the concentration of the HCl solution?

Accepted Answer

$$0.0833\ 	ext{M}$$

Question 6

Which of the following is a correct application of the law of conservation of energy in a chemical reaction?

Accepted Answer

The total energy of the system and surroundings remains constant during the reaction.

Question 7

Which equation correctly represents the calculation of heat transfer ($$q) $$for a substance undergoing a temperature change?

Accepted Answer

$$q = m c \Delta T$$

Question 8

A gas occupies 2.50 L at 1.00 atm and 300 K. What volume will it occupy at 2.00 atm and 300 K? (Assume ideal gas behavior.)

Accepted Answer

$$1.25\ 	ext{L}$$

Question 9

Which of the following best describes an endothermic process?

Accepted Answer

A process in which the system absorbs heat from the surroundings.

Question 10

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

Accepted Answer

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

Question 11

Which of the following is NOT a property of an ideal gas according to the kinetic molecular theory?

Accepted Answer

Gas particles exert attractive forces on each other.

Question 12

Which of the following equations is used to relate the rate of effusion of two gases to their molar masses?

Accepted Answer

$$\dfrac{	ext{Rate}_1}{	ext{Rate}_2} = \sqrt{\dfrac{M_2$}{M_1$}}$$

Question 13

A chemical reaction has $$\Delta H = -150\ 	ext{kJ}. $$Which statement is true about this reaction?

Accepted Answer

The reaction is exothermic and releases heat to the surroundings.

Question 14

Which of the following is the correct formula for calculating the total pressure of a mixture of gases?

Accepted Answer

$$P_{	ext{total}} = P_1$ + P_2$ + P_3$ + \ldots$$

Question 15

Which of the following is the correct balanced chemical equation for the reaction between sodium sulfate and barium chloride to form barium sulfate and sodium chloride?

Accepted Answer

$$	ext{Na}_2	ext{SO}_4 (aq) + 	ext{BaCl}_2 (aq) ightarrow 	ext{BaSO}_4 (s) + 2	ext{NaCl} (aq)$$

Question 16

Which of the following is the correct formula for calculating the change in enthalpy ($$\Delta H) $$using Hess's Law?

Accepted Answer

$$\Delta H = \sum \Delta H_{	ext{products}} - \sum \Delta H_{	ext{reactants}}$$

Question 17

Which of the following statements about oxidation and reduction is correct?

Accepted Answer

Oxidation is the loss of electrons, and reduction is the gain of electrons.

Question 18

A sample of gas at STP contains 2.00 moles. What is its volume?

Accepted Answer

$$44.8\ 	ext{L}$$

Question 19

Which of the following is the correct formula for calculating mole fraction ($$X_A) of $$component A in a mixture?

Accepted Answer

$$X_A = \dfrac{n_A}{n_{	ext{total}}}$$

General Chemistry I: Core Concepts and Problem-Solving Guide (Chapters 4–7)

Guida di studio - Domande di pratica

Study guide - Flashcard