Question 1

A reaction is found to be first order in A and second order in B. Which of the following is the correct rate law for the reaction?

Accepted Answer

$$	ext{rate} = k[A][B]^2$$

Question 2

The half-life for a first-order reaction is 10 minutes. How much of a 100 g sample remains after 30 minutes?

Accepted Answer

$$12.5\ 	ext{g}$$

Question 3

Which of the following statements about a catalyst is correct?

Accepted Answer

A catalyst lowers the activation energy of a reaction, increasing the reaction rate.

Question 4

A solution is prepared by dissolving 10 g of NaCl in 100 g of water. Which colligative property will be affected, and how?

Accepted Answer

The boiling point of the solution will increase.

Question 5

Which equation correctly relates the change in free energy to enthalpy and entropy at constant temperature?

Accepted Answer

$$\Delta G = \Delta H - T\Delta S$$

Question 6

At 25°C, the equilibrium constant $$K_c$$ for a reaction is $$1.0 	imes 10^5$. What does this indicate about the reaction at equilibrium?

Accepted Answer

Products are favored over reactants.

Question 7

Which of the following best describes the effect of adding a common ion to a saturated solution of a sparingly soluble salt?

Accepted Answer

The solubility of the salt decreases due to the common ion effect.

Question 8

A buffer solution is made by mixing equal moles of acetic acid ($$\mathrm{CH_3COOH}) $$and sodium acetate ($$\mathrm{CH_3COONa}). $$What will happen to the pH if a small amount of HCl is added?

Accepted Answer

The pH will decrease slightly, but the buffer will resist large changes.

Question 9

Which of the following is the correct Nernst equation for a half-cell reaction at 25°C?

Accepted Answer

$$E = E^\circ - \frac{0.0592}{n} \log Q$$

Question 10

Which of the following best explains why transition metals often form colored compounds?

Accepted Answer

They have partially filled d orbitals that allow d-d electronic transitions.

Question 11

A 0.1 M solution of a weak acid HA has a pH of 3. What is the acid dissociation constant $$K_a$$ for HA?

Accepted Answer

$$K_a = 1 	imes 10$$^{-5}$$

Question 12

Which of the following statements about entropy ($$S) is $$correct?

Accepted Answer

Entropy is a measure of the disorder or randomness of a system.

Question 13

During a titration of a strong acid with a strong base, what is the pH at the equivalence point?

Accepted Answer

The pH is 7.

Question 14

Which of the following is the correct expression for the solubility product constant ($$K_{sp}) $$for $$\mathrm{$$CaF_2$$}$$?

Accepted Answer

$$K_{sp} = [Ca$$^{2+}$$][F^-]^2$$

Question 15

Which of the following best describes the effect of increasing temperature on the rate constant $$k$$ for most chemical reactions?

Accepted Answer

The rate constant increases because more molecules have energy greater than the activation energy.

Question 16

A voltaic cell is constructed using a Zn/Zn$$^{2+}$$ half-cell and a Cu/Cu$$^{2+}$$ half-cell. Which statement is correct?

Accepted Answer

Electrons flow from the Zn electrode to the Cu electrode.

Question 17

Which of the following is the correct relationship between $$K_p$$ and $$K_c$$ for a gaseous reaction?

Accepted Answer

$$K_p = K_c(RT$$)^{\Delta n}$$

Question 18

Which of the following is true about the Henderson-Hasselbalch equation?

Accepted Answer

$$\mathrm{pH} = \mathrm{p}K_a + \log \left( \frac{[	ext{A}^-]}{[	ext{HA}]} ight)$$

Question 19

Which of the following best describes the coordination number in a transition metal complex?

Accepted Answer

The number of ligand donor atoms directly bonded to the central metal ion.

Question 20

Which of the following is the correct expression for the osmotic pressure ($$\Pi) of a $$dilute solution?

Accepted Answer

$$\Pi = MRT$$

CHE 132 Final Exam Study Guide: Kinetics, Colligative Properties, Entropy, Free Energy, Equilibrium, Acid-Base Chemistry, Electrochemistry, and Transition Metals

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