Question 1

Which of the following best describes a Lewis acid?

Accepted Answer

A substance that accepts an electron pair from another substance.

Question 2

Given the reaction: $$\mathrm{NH_3$ + H_2O \rightarrow NH_4$^+ + OH^-}$$, which species is the conjugate acid of $$\mathrm{NH_3$}$$?

Accepted Answer

$$\mathrm{NH_4$^+}$$

Question 3

Which of the following substances is amphoteric?

Accepted Answer

$$\mathrm{H_2O}$$

Question 4

Order the following binary acids in terms of increasing acid strength: $$\mathrm{HF}$$, $$\mathrm{HCl}$$, $$\mathrm{HI}.$$

Accepted Answer

$$\mathrm{HF \u003c HCl \u003c HI}$$

Question 5

A solution has $$[\mathrm{H_3O^+}] = 1.0 	imes 10$$^{-4}$$\ \mathrm{M}. $$What is the pH of the solution?

Accepted Answer

$$\mathrm{pH} = 4.0$$

Question 6

Which of the following statements about strong acids is correct?

Accepted Answer

Strong acids have high $$K_a$$ values and dissociate completely in water.

Question 7

Calculate the pH of a $$0.01\ \mathrm{M}$$ solution of $$\mathrm{NaOH} (a $$strong base).

Accepted Answer

$$\mathrm{pH} = 12$$

Question 8

Which of the following pairs could be used to make a buffer solution?

Accepted Answer

$$\mathrm{CH_3COOH}$$ and $$\mathrm{CH_3COONa}$$

Question 9

Which salt will produce a basic solution when dissolved in water?

Accepted Answer

$$\mathrm{NaCH_3COO}$$

Question 10

A buffer is prepared using $$\mathrm{0.1\ M}$$ acetic acid ($$\mathrm{CH_3COOH}) $$and $$\mathrm{0.1\ M}$$ sodium acetate ($$\mathrm{CH_3COONa}). If$$ $$K_a$$ for acetic acid is $$1.8 	imes 10$$^{-5}$$, what is the pH of the buffer?

Accepted Answer

$$\mathrm{pH} = 4.74$$

Question 11

Which of the following best explains why the equivalence point of a titration between a weak acid and a strong base is greater than 7?

Accepted Answer

The conjugate base of the weak acid hydrolyzes to produce $$\mathrm{OH^-}$$ ions.

Question 12

Which indicator would be most appropriate for a titration of $$\mathrm{CH_3COOH}$$ with $$\mathrm{NaOH}$$?

Accepted Answer

Phenolphthalein (pH range 8.2–10.0)

Question 13

Which of the following processes is spontaneous?

Accepted Answer

Iron rusting in moist air

Question 14

Which statement best describes the Second Law of Thermodynamics?

Accepted Answer

The entropy of the universe always increases in a spontaneous process.

Question 15

Given the reaction $$\mathrm{2H_2 + O_2$ \rightarrow 2H_2O}$$, what is the change in entropy ($$\Delta S) $$likely to be?

Accepted Answer

$$\Delta S \u003c 0$$

Question 16

Which equation relates Gibbs Free Energy to enthalpy and entropy?

Accepted Answer

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

Question 17

Assign the oxidation number to sulfur in $$\mathrm{SO_4$^{2-}}.$$

Accepted Answer

$$+6$$

Question 18

Which of the following metals will react with $$\mathrm{HCl} to $$produce $$\mathrm{H_2$}$$ gas?

Accepted Answer

Zinc ($$\mathrm{Zn})$$

Question 19

Which of the following statements about the reduction of hydrogen is correct?

Accepted Answer

The standard reduction potential of hydrogen is $$0.00\ \mathrm{V} by $$definition.

Acids, Bases, Thermodynamics, Electrochemistry, and Organic Chemistry: Comprehensive Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard