Name______________________________________________________period______IB chemistry Ch. 8: acid/bases
1. What is the difference between the Arrhenius and the Bronsted-Lowry definition of an acid?
Arrhenious acids give H+ in water
Bronsted-Lowry acids are proton donors
2. NH 3 (g) and HCl(g) react to form the ionic solid NH 4 Cl(s). Which substance is the bronsted-Lowry acid in this
reaction? Which is the Bronsted-Lowry base?
Acid- HCl; base-NH 3
3. What is the difference between the Arrhenius and the Bronsted-Lowry definition of a base?
Arrhenius bases give OH- in water
Bronsted-Lowry bases are proton acceptors
4. Give the conjugate base of the following
a. H 2 SO 3
b. HC 2 H 3 O 2
c. H 2 AsO 4 d. NH 4 +
e. H 2 O
2HSO 3
C2H3O2
HAsO 4
NH 3
OH5. Give the conjugate acid of the following
a. C 7 H 5 O 2 b. BrO 2 c. NH 3
d. H 2 AsO 4 e. CO 3 2HC 7 H 5 O 2
HBrO 2
NH 4 +
H 3 AsO 4
HCO 3 6. Identify the Bronsted-Lowry acid and the Bronsted-Lowry base in each reaction and the conjugate acid/base pair
a. NH 4 + + CN-  HCN + NH 3
acid
base
conjugate base conjugate acid
b. (CH 3 ) 3 N + H 2 O  (CH 3 ) 3 NH+ + OHbase
acid
conjugate acid conjugate base
c. HCHO 2 + PO 4  CHO 2 - + HPO 4 2acid
base
3-
conjugate base conjugate acid
7. a. HC 2 O 4 - is amphoteric. Write a balanced equation showing how it acts as an acid toward water and another
equation showing how it acts as a base toward water.
HC 2 O 4 - + H 2 O  H 2 C 2 O 4 + OHHC 2 O 4 - + H 2 O  C 2 O 4 2-+ H 3 O+
b. What is the conjugate acid of HC 2 O 4 - ? What is the conjugate base?
H 2 C 2 O 4 ; C 2 O 4 28. What color is litmus in an acid? In a base? Red; blue
9. What color is phenolphthalein in an acid? In a base? Clear; pink
10. Write equations for the following reactions
a. sulfuric acid + copper(II) oxide
H 2 SO 4 + CuO  CuSO 4 + H 2 O
b. nitric acid + sodium hydrogen carbonate
HNO 3 + NaHCO 3  NaNO 3 + H 2 O + CO 2
c. phosphoric acid + potassium hydroxide
H 3 PO 4 + 3KOH  K 3 PO 4 + 3H 2 O
d. ethanoic acid + aluminum
6CH 3 COOH + 2Al  2Al(CH 3 OO) 3 + 3H 2
e. hydrochloric acid + calcium hydroxide
2HCl + Ca(OH) 2  CaCl 2 + 2H 2 O
f. hydrobromic acid + magnesium carbonate
2HBr + MgCO 3  MgBr 2 + CO 2 + H 2 O
11. What are some properties of acids? Taste sour, turns red in litmus
12. What are some properties of bases? Taste bitter, turns blue in litmus, slippery
13. Why are strong acids also strong electrolytes (strong conductors or electricity)?
completely ionize in water so there are a lot of ions to conduct electricity
14. Name each of the following and label them as a weak/strong acid or weak/strong base
a. H 3 PO 4
b. Ca(OH) 2
c. Al(OH) 3
d. HNO 3
e. NH 3
f. LiOH
a.Phosphoric acid, weak
b.calcium hydroxide, strong base
c. aluminum hydroxide, weak base
d. nitric acid, strong
e. ammonia, weak base
f. lithium hydroxide, strong base
15. Which of the following solutions will be the poorest conductor of electricity?
a. HCl
b. CH 3 COOH
c. NaOH
d. NaCl
+
16. Which of the following has the highest concentration of [H ]? 0.1 mol dm-3 HCl or 0.1 mol dm-3 HF
17. What is the [H+] in each?
a. 0.5 mol dm-3 HCl
b. 0.002 mol dm-3 HNO 3
-3
0.5 mol dm
0.002 mol dm-3
18. What is the [OH-] in each?
b. 0.5 mol dm-3 NaOH
b. 0.03 mol dm-3 Ca(OH) 2
-3
0.5 mol dm
0.06 mol dm-3
19. What is the pH of a 0.0034 M HNO 3 solution?
2.5
20. What is the hydrogen ion concentration of a solution with a pH of 5? Is it an acid or a base?
1 x 10-5 mol dm-3; acid
21. Which of the following solutions would have the lowest pH?
0.10 M HCl, 0.009 M HNO 3 , 0.340 M HBr
22. Determine the pH of the following solutions and label if they are acidic or basic
a. [H+] = 1 x 10 -6
b. [OH-] = 1 x 10 -3
c. [H+] = 2.3 x 10 -3
d. [OH-] = 3.4 x 10 -6
6 ; acidic
11; basic
2.64; acidic
8.5; basic
23. determine the [H+] for the following solution and label if they are acidic or basic
a. [OH-] = 1 x 10 -8
b. [OH-] = 2.3 x 10 -6
c. pH = 2
1 x 10-6, acidic
4 x 10 -9 , basic
1 x 10 -2, acidic
d. pOH = 5
e. pH = 3.4
f. pOH = 4.2
-9
-4
1 x 10 , basic
4.0 x 10 , acidic
1.6 x 10 -10, basic
24. Determine the pH of the following solutions (label if they are acidic or basic)
a. [H+] = 1.0 x 10 -12
b. [H+] = 2.3 x 10 -3
c. [OH-] = 1.0 x 10 -11
12; basic
2.6; acidic
3; acidic
d. [OH-] = 6.7 x 10 -8
6.8; acidic
g. 1 x 10 -2 mol dm-3 NaOH
12;basic
j. 0.001 mol dm-3 HI 3; acidic
e. 1 x 10 -2 mol dm-3 HNO 3
f. 3.98 x 10 -4 mol dm-3 HCl
2; acidic
3.4; acidic
-2
-3
+
h. 8.9 x 10 mol dm Ba(OH) 2 i. [H ] = 1 x 10 -7
13.2; basic
7; neutral
25. Which of the solutions in the previous problem is the most acidic? Most basic?
E; h
26. Which of the solutions in #27 has the highest hydronium ion concentration? Highest hydroxide ion
concentration?
E; h
27. Determine the [H+] for each of the following
a. [OH-] = 2.3 x 10 -4
b. pOH = 3.11
c. pH = 9
-11
-11
4.34 x 10 M
1.29 x 10 M
1 x 10 -9 M
-3
d. 0.0001 mol dm KOH
e. pOH = 2
f. 0.003 mol dm-3 HBr
1 x 10 -10 M
1 x 10 -12 M
0.003 M
28. When equal concentrations of a strong and a weak acid are compared, which of the following measurements will be the
same?
I.
The volume of base used to neutralized the acid
II.
The electrical conductivity
III.
The rate of the reaction with calcium carbonate
b. I and II only
c. I, II, and III
d. none of I, II, or III
a. I only
-
29. CH 3 OH is a very weak bronsted-lowry acid. What is true of the ion CH 3 O ?
a. It is a good proton donor
b. It will be present in high concentration in CH 3 OH at equilibrium
c. It is a strong bronsted-Lowry base
d. It is a stronger bronsted-Lowry acid than CH 3 O
30. Which of these reduces the production of acid rain?
I.
Removing SO 2 from power station emissions
II.
Neutralizing acidified lakes with lime
III.
Switching to renewable energy sources
c. II and III
a. I and II
b. I and III
31. Which of the following occurs as a result of acid deposition?
2+
I.
Ca ions are washed out of the soil
II.
Thermal expansion of oceans
III.
Fish are killed due to high levels of aluminum in the water
c. II and III
a. I and II
b. I and III
d. I, II, and III
d. I, II, and III
32. Weak acids in the environment may cause damage. Identify a weak acid in the environment and outline one of its effect.
sulfurous acid/H 2 SO 3 corrodes marble / limestone buildings / statues / leaching in soils / harms/kills plants OR
nitrous acid/HNO 2 corrodes marble / limestone buildings / statues / leaching in soils / harms/kills plants OR
carbonic acid/H 2 CO 3 corrodes marble / limestone buildings / statues / acidification of lakes
33. A) Describe the difference in dispersion between dry acid deposition and wet acid deposition.
Dry acid deposition typically occurs close to the source of emission. Wet acid deposition is dispersed over a
much larger area and distance from the emission source
b) Explain the physical and chemical processes involved in the development of wet acid deposition.
The acid is formed in the air from sulfur dioxide (SO 2 ) and nitrogen oxide (NO) which are emitted by thermal power
stations, industry and motor vehicles. A major source is the burning of fossil fuels, particularly in coal-fired power
stations. Pollutants are carried by prevailing winds and converted (oxidized) into sulfuric acid (H 2 SO 4 ) and nitric acid
(HNO 3 ). These are then dissolved in cloud droplets (rain, snow, mist, hail) and this precipitation may fall to the ground
as dilute forms of sulfuric acid and nitric acid. The dissolved acids consist of sulfate ions, nitrate ions and hydrogen ions
34. The table gives some substances found in air
Name
Formula
Sulfur dioxide
SO 2
Nitrogen monoxide
NO
Particulates
a. Identify the pollutant(s) which contribute(s) to acid rain SO 2 and NO
b.
Identify the pollutant(s) which come(s) mainly from power stations. SO 2 and particulates
c.
The presence of one of these pollutants makes the ill effects of the others worse. Identify the pollutant and explain
why it has this effect. Particulates act as catalysts in the production of secondary pollutants.
d.
Emissions of one of these pollutants have been controlled by reaction with calcium oxide. Identify this pollutant and
write an equation for the reaction with calcium oxide
SO 2 (g): CaO(s) + SO 2 (g) → CaSO 3 (g)
e.
Identify the pollutants that come primarily from motor vehicles and describe the basis for their production.
NO: formed from the combination of nitrogen and oxygen at the high temperature of internal combustion
engines.
Review
31. Write a balanced reaction when magnesium metal reacts with hydrobromic acid
Mg + 2HBr  MgBr 2 + H 2
b. How many moles of each product are produced if 5.4 mol of magnesium react?
5.4 mol of magnesium bromide and 5.4 mol of hydrogen
32. a. Write a balanced reaction when nitric acid react with aluminum hydroxide
3HNO 3 + Al(OH) 3  3H 2 O + Al(NO 3 ) 3
b. How many grams of nitric acid are needed to react with 2.3 mol of aluminum hydroxide?
430 g
33. Tell the shape of each, tell if they are polar or nonpolar, tell what intermolecular forces hold them together, and
tell which one would have the lowest boiling point.
a. H 2 O
Bent
Polar
Hydrogen bond and LD
b. NH 3
c. CH 4
trigonal pyramidal
tetrahedral
polar
nonpolar
hydrogen bond and LD
London dispersion
CH 4 has the lowest boiling point
34. What is the difference between and exothermic and endothermic reaction?
Exothermic releases energy and feels warm; endothermic absorbs energy and feels cold
35. H 2 + F 2 <-> 2HF ΔH -538 kJ
b. Will raising the temperature cause the amount of product to increase? no
c. How will the equilibrium shift if hydrogen is added to the reaction? right
d. How will the equilibrium shift if HF is removed from the reaction? right
e. What will happen to the amount of hydrogen if the temperature is decreased? decreases
f. Will the temperature of the surroundings increase or decrease as the reaction moves forward? increases
36. How many cm3 of 0.340 M HBr would be needed to titrate 14.91 cm3 of 0.265 mol dm-3 Mg(OH) 2 ? 23.2 cm3
37. What is the concentration of sulfuric acid solution if 34.1 cm3 of it is needed to reach the endpoint when titrated
with 14.3 cm3 of 0.876 mol dm-3 aluminum hydroxide? 0.551 mol dm-3