Question :
1.Which of the following statements concerning acids and bases FALSE?
A) : 1318415
1.Which of the following statements concerning acids and bases is FALSE?
A) A Brønsted-Lowry acid is a proton (H+) donor.
B) A Brønsted-Lowry base is a proton (H+) acceptor.
C) Reactions between acids and bases involve the transfer of a proton (H+) from the acid to the base.
D) Addition of an acid to water decreases the pH of the solution.
E) Addition of a base to water increases the hydronium ion concentration of the solution.
2.Which statement correctly describes conjugate acids and bases according to the Brønsted-Lowry theory?
A) A conjugate base is the species formed when an acid donates a proton; a conjugate acid is the species formed when a base accepts a proton.
B) A conjugate base is the species formed when an acid accepts a proton; a conjugate acid is the species formed when a base donates a proton.
C) A conjugate acid is the species formed when an acid donates a proton; a conjugate base is the species formed when a base accepts a proton.
D) A conjugate acid is an acid that does not completely transfer a proton to water; a conjugate base is a base that does not completely accept a proton from water.
E) A conjugate acid is the solution formed when an acid is added to water; a conjugate base is the solution formed when a base is added to water.
3.Which statement concerning the relative strength of acids is FALSE?
A) Strong and weak acids differ in their extent of proton transfer to water.
B) Strong acids are good proton donors; weak acids are poor proton donors.
C) A strong acid completely transfers its protons to water; a weak acid only partially transfers its protons to water.
D) Strong acids produce strong conjugate bases; weak acids produce weak conjugate bases.
E) A strong acid produces more hydronium ions in water than a weak acid of the same concentration.
4.Which of the following best represents the autoionization, or self-ionization, of water?
A) H2O(l) ??H+(aq) ????−(aq)
B) 2H2O(l) 2H2(aq) + O2(aq)
C) 2H2O(l) H3O+(aq) + OH–(aq)
D) H2O(l) ??H2(aq) ???2−(aq)
E) H+(aq) ????−(aq) ??H2O(l)
5.Which of the following correctly describes what is meant by the term neutralization?
A) the gain of electrons to form an uncharged species
B) the loss of electrons to form an uncharged species
C) the reaction between an acid and a base to form salt and water
D) the transfer of electrons from an acid to a base
E) the reaction between an oxidizing agent and a reducing agent
6.What is always a characteristic of a solution that contains a buffer?
A) The solution is neutral and has a pH of 7.
B) The solution contains a small amount of solute dissolved in a large volume of solvent.
C) The solution has been diluted by the addition of solvent.
D) The solution resists large changes in pH when small amounts of acids or bases are added.
E) The solution maintains a constant pH value; no amount of added acid or base can change the pH.
7.Consider the following generalized buffer solution equilibrium:
BH+(aq) + H2O(l) H3O+(aq) + B(aq)
When a small amount of a strong base such as sodium hydroxide is added to the solution, which of the four species shown would experience an increase in concentration? (Hint: Use Le Chatelier’s principle.)
A) BH+
B) H2O
C) H3O+
D) B
E) None of the species would increase in concentration.
8.What is true about a solution whose pH is less than 7?
A) It has a hydronium ion concentration less than 1 × 10−7.
B) It has a hydronium ion concentration that is higher than pure water itself.
C) It has a hydroxide ion concentration equal to its hydronium ion concentration.
D) It is a solution that requires a buffer.
E) It is a basic solution.
9.A particular buffer solution consists of a weak acid and its conjugate base. How could this buffer solution be modified so as to increase its buffer capacity against added base?
A) Increase the concentration of the weak acid.
B) Increase the concentration of its conjugate base.
C) Use a strong base and its conjugate acid instead.
D) Use a strong acid and its conjugate base instead.
E) Make the concentrations of the weak acid and its conjugate base equal.
10.A buffer solution contains acetic acid (HC2H3O2) at a concentration of 0.225 M and sodium acetate (NaC2H3O2) at a concentration of 0.164 M. The value of Ka for acetic acid is 1.75 ? 10−5. What is the pH of this buffer solution?
A) 0.137
B) 0.862
C) 2.40
D) 4.62
E) 4.76
Page 1
