Deck 9: Acid-Base Reactions

Question 1

What is the salt formed when an HCl solution reacts with Mg(OH)₂?

A) MgCl₂
B) Mg₂Cl
C) MgCl
D) Mg₂Cl₂

Answer 1

MgCl₂

Question 2

A solution with pH = 4 has

A) relatively high concentration of OH^-.
B) relatively low concentration of H₃O⁺.
C) zero concentration of OH^-.
D) relatively high concentration of H₃O⁺.

Answer 2

relatively high concentration of H₃O⁺.

Question 3

Which of the following equations represents the neutralization of acidic gastric fluid?

A) 2 HNO₃(aq) + Mg(OH)₂ (aq) $\to$ Mg(NO₃)₂(aq) + 2 H₂O(l)
B) H⁺(aq) + OH⁺(aq) $\to$ H₂O(l)
C) 2 HCl(aq) + Mg(OH)₂(aq) $\to$ 2 H₂O(l) + MgCl₂(aq)
D) NaOH(aq) + H₂O(l) $\to$ Na⁺(aq) + OH^-(aq)

Answer 3

2 HCl(aq) + Mg(OH)₂(aq) $\to$ 2 H₂O(l) + MgCl₂(aq)

Question 4

Which reactant is the base, in the following reaction? NH₃(g) + H₂O(l) $\to$ NH₄⁺(aq) + OH^-(aq)

A) OH^-
B) NH₄⁺
C) H₂O
D) NH₃

Question 5

Which of the following is associated with stomach fluid?

A) HNO₃
B) H₃PO₄
C) HCl
D) H₃PO₄ and HCl

Question 6

An ion commonly found in many antacids is

A) OH^-.
B) H₃O⁺.
C) SO₄^2-.
D) NH₄⁺.

Question 7

Which of the following indicates a basic solution?

A) pH = 7
B) pH < 7
C) pH = 11
D) pH = 0

Question 8

Which one of the following is the acid in vinegar?

A) acetic acid
B) citric acid
C) muriatic acid
D) ascorbic acid

Question 9

Which of the following is a property of bases?

A) feel slippery to the touch
B) have pH below 7
C) turn blue litmus red
D) neutralize substances like NaOH

Question 10

Which of the following equations represents a neutralization reaction?

A) KCl(aq) + H₂O(l) $\to$ K⁺(aq) + Cl^- (aq)
B) H⁺(aq) + OH^- (aq) $\to$ H₂O(l)
C) HCl(aq) + H₂O(l) $\to$ H₃O⁺(aq) + Cl^-(aq)
D) NaOH(aq) + H₂O(l) $\to$ Na⁺(aq) + OH^- (aq)

Question 11

The substance Ca(OH)₂ is

A) an acid.
B) a hydrate.
C) a base.
D) an oxide.

Question 12

What volume (in liters) of 1 M NaOH contains 40 g sodium hydroxide?

A) 100 L
B) 1 L
C) 10 L
D) 1000 L

Question 13

Which common substance would have a pH less than 7?

A) milk of magnesia
B) wine
C) borax solution
D) bleach

Question 14

What is the pH of a 0.001 M HCl solution?

A) 10^-3
B) 0.001
C) 3
D) -3

Question 15

A buffer is a mixture that

A) maintains pH.
B) causes a solution not to conduct electricity.
C) neutralize salts.
D) causes high blood pressure.

Question 16

Red cabbage can be used as a dye indicator used to measure pH, in basic solutions it has a_________ color.

A) pink
B) yellow
C) red
D) colorless

Question 17

Carbonic acid, H₂CO₃(aq) is present in

A) eye drops.
B) milk.
C) carbonated beverages.
D) vinegar.

Question 18

What is the pH of a 0.0001 M HCl solution?

A) 10^-4
B) 0.0001
C) - 4
D) 4

Question 19

In an acidic solution,

A) [H₃O⁺] is greater than [OH^-].
B) [H₃O⁺] equals [OH^-].
C) [OH^-] is greater than [H₃O⁺].
D) none of these

Question 20

The strength of an acid is related to its

A) extent of ionization.
B) reaction with a salt.
C) concentration.
D) commercial ranking in the economy.

Question 21

Which of the following carries the electrical current in an aqueous NaCl solution?

A) electrons
B) ions
C) the solvent - water
D) none of the above

Question 22

Which of the following is the formula of a salt formed from Ca²⁺ and PO₄^3- ions?

A) CaPO₄
B) Ca₂(PO₄)₃
C) Ca₃(PO₄)₂
D) Ca₃P₂O₄

Question 23

Which of the following is true about a solution with pH = 5?

A) The solution is basic.
B) The OH^- concentration is greater than the H⁺ concentration.
C) The solution is acidic.
D) both a and b

Question 24

Which of the following is the weak acid?

A) HCl
B) H₂SO₄
C) HNO₃
D) HC₂H₃O₂

Question 25

Which of the following is true about a solution with pH = 8?

A) The solution is basic.
B) The H⁺ concentration equals 0.00000001 M.
C) The OH^- concentration is great than the H⁺ concentration.
D) all of these

Question 26

How many acidic hydrogen atoms are in one molecule of acetic acid, CH₃COOH?

A) one
B) two
C) three
D) four

Question 27

What substance is found in corrosive cleaners?

A) sulfuric acid, H₂SO₄
B) hydrochloric acid, HCl
C) sodium hydroxide, NaOH
D) acetic acid, CH₃COOH

Question 28

Hydrogen chloride gas has polar covalent molecules. An aqueous solution of HCl conducts electricity. How?

A) HCl ionizes in water.
B) HCl molecules carry electrons from one electrode to the other electrode.
C) water molecules carry electrons from one electrode to the other electrode.
D) HCl molecules and water molecules carry the current.

Question 29

If 3.0 mol of a substance are dissolved in 500 mL (0.50 L) of solution, the molarity of this solution is

A) 3.0 M.
B) 1.5 M.
C) 3.5 M.
D) 6.0 M.

Question 30

How many moles of phosphoric acid, H₃PO₄ are in 0.50 L of 6.0 M H₃PO₄(aq)?

A) 6.5 mol
B) 24 mol
C) 12 mol
D) 3.0 mol

Question 31

A base is

A) an OH^- ion donor.
B) a hydrogen ion donor.
C) a substance like magnesium hydroxide, Mg(OH)₂.
D) both a and c

Question 32

All aqueous solutions of electrolytes must by definition

A) be acids.
B) be neutral.
C) contain no ions.
D) conduct electricity.

Question 33

What acid is found in stomach fluid?

A) sulfuric acid, H₂SO₄
B) hydrochloric acid, HCl
C) citric acid, HOC(COOH)(CH₂COOH)₂
D) acetic acid, CH₃COOH

Question 34

Chemical buffering systems

A) maintain constant pH.
B) consist of a acid and a base pair.
C) absorb added H⁺ or OH^- ions.
D) Buffers do all of the above.

Question 35

What is the pH for a solution with hydrogen ion molarity of 0.01?

A) -2
B) 2
C) 100
D) 10^-2

Question 36

Why is pure water neutral?

A) Pure water has no H⁺ ions and no OH^- ions.
B) Pure water has equal numbers of H⁺ ions and OH^- ions
C) Pure water has no dissolved carbon dioxide
D) The pH of pure water at 25 ^$\circ$ C is 0.

Question 37

An acid ion pair such as H₂CO₃ and HCO₃^- qualifies as a

A) strong acid-strong base pair.
B) buffer system.
C) substitute for hemoglobin.
D) acid -base pair.

Question 38

The symbol, M, related to concentration of solution, refers to

A) much meaning a very concentrated solution.
B) molal concentration.
C) moles of solute dissolved in one liter of solution.
D) mixed meaning the solution has been stirred well.

Question 39

When H₂SO₃ dissolves in water, what are the solute particles in the solution?

A) H, S, O
B) H⁺, S⁺ and O^2-
C) H⁺, HSO₃^- and SO₃^2-
D) H₂²⁺ and SO₃^2-

Question 40

H₃O⁺ is the

A) hydronium ion.
B) hydrogen ion.
C) proton.
D) hydridium ion.

Question 41

A solution with pH 7.0 is neutral because the concentration of the hydroxide ions and hydronium ions are equal

Question 42

Vitamin C and aspirin are both acidic substances.

Question 43

Identify the acid in the following reaction. NH₃(g) + H₂O(l) $\to$ NH₄⁺(aq) + OH^-(aq)

A) OH^-
B) NH₄⁺
C) H₂O
D) NH₃

Question 44

You need to make an aqueous solution of 0.139M aluminum nitrate, Al(NO₃)₃ for an experiment in the lab, using a 300. mL volumetric flask. How much solid aluminum nitrate (molar mass = 213.012 g) should you add to the flask?

A) 0.0101 g
B) 0.0417 g
C) 1.96 g
D) 8.88 g
E) 98.7 g

Question 45

What is the pH of a solution with a [H₃O⁺] = 1.0 $\times$ 10^-10?

A) 10^-10
B) 1.0
C) -10
D) 10

Question 46

What is the pH of a 0.0525 M HCl solution?

A) 5.25
B) 0.0525
C) 1.28
D) 3.00

Question 47

Which of the following are paired incorrectly?

A) HBr ; strong acid
B) Ca(OH)₂ ; strong base
C) HC₂H₃O₂ ; weak acid
D) KOH ; strong base
E) HNO₃ ; weak acid

Question 48

Oven cleaner is a basic or alkaline substance while gastric fluid is acidic.

Question 49

What is the concentration difference between pH = 10 and pH = 7?

A) 100
B) 0.001
C) 3
D) 1000

Question 50

Both HCl and sulfuric acids are strong acids.

Question 51

Which pair would make a good buffer?

A) H⁺/OH^-
B) Na⁺ /Cl^-
C) HPO₄^2- /PO₄^3-
D) Na⁺ /OH^-

Question 52

What volume of 0.378 M hydroiodic acid (HI) is required to neutralize 21.6 mL of 0.520 M barium hydroxide, Ba(OH)₂?

A) 5.83 mL
B) 15.6 mL
C) 29.7 mL
D) 59.4 mL
E) 80.0 mL

Question 53

What is the molarity of a solution when 15.0 g of NaCl is dissolved to a final volume of 500. mL with water?

A) 0.513 M
B) 117 M
C) 0.0300 M
D) 30.0 M

Question 54

What is the pH of a 0.00125 M NaOH solution?

A) 2.90
B) 11.1
C) 12.5
D) 1.25

Question 55

The formula for the hydroxide ion is OH⁺.

Question 56

KOH and NaOH are both bases but NaOH is a weak base while KOH is a strong base.

Question 57

A change in pH from 3.0 to 5.0 represents

A) a 10 fold increase in acidity.
B) a 10 fold decrease in acidity.
C) a 100 fold increase in acidity.
D) a 100 fold decrease in acidity.
E) a decrease in acidity by a factor of 2.

Question 58

Consider the image below. If the pH registered is that of a buffer solution, which of the following describes what will happen if some HCl is added the solution?

A) The pH will increase slightly.
B) The pH will decrease slightly.
C) The pH will increase drastically.
D) The pH will decrease drastically.

Question 59

What is the hydronium concentration with pH = 9.5?

A) 3.16 $\times$ 10^-10
B) 9.50 $\times$ 10^-10
C) 9.15
D) 3.16 $\times$ 10¹⁰

Question 60

The compound ammonia, NH₃, is a weak base when dissolved in water. Which of the following is the correct equation for the reaction of ammonia in water?

A) NH₃(aq) + H₂O(l)NH₄⁺(aq) + OH^-(aq)
B) NH₃(aq) + H₂O(l)NH₂^-(aq) + H₃O⁺(aq)
C) NH₃(aq) + H₃O⁺(aq)NH₄⁺(aq) + H₂O(l)
D) NH₃(aq) + OH^-(aq)NH₂^-(aq) + H₂O(l)
E) "NH₃(aq) + H₂O(l)NH₂^-(aq) + H₃O⁺(aq)"

Question 61

Aqueous solutions can be classified as acidic, basic, or neutral. Use these three terms of complete the following statements.
A solution with a pH of 5.05 is ___________.

Question 62

Aqueous solutions can be classified as acidic, basic, or neutral. Use these three terms of complete the following statements.
Consider the image below. The sample being tested with the pH meter is _________.

Question 63

An acid turns blue litmus red and a base has a slippery feel.

Question 64

Aqueous solutions can be classified as acidic, basic, or neutral. Use these three terms of complete the following statements.
If 0.50 mol of HBr is added to 0.65 mol of NaOH, the resulting solution will be __________.

Question 65

Aqueous solutions can be classified as acidic, basic, or neutral. Use these three terms of complete the following statements.
Consider the image below. The sample being tested with the pH paper is _________.

Question 66

Aqueous solutions can be classified as acidic, basic, or neutral. Use these three terms of complete the following statements.
An aqueous solution containing an unknown substance has a hydronium ion concentration of 7.56 × 10^-9 M, this solution is ___________.

Question 67

A base is the common component found in Tums^®, Rolaids^®, Alka-Seltzer^®, and Phillips' Milk of Magnesia^®.

Question 68

A solution of Na₂CO₃ in water will have a pH greater than 7.