Name______________________________________________________period______IB chemistry Ch. 8: acid/bases

Transcription

Name______________________________________________________period______IB chemistry Ch. 8: acid/bases
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. NH3(g) and HCl(g) react to form the ionic solid NH4Cl(s). Which substance is the bronsted-Lowry acid in this
reaction? Which is the Bronsted-Lowry base?
Acid- HCl; base-NH3
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. H2SO3
b. HC2H3O2
c. H2AsO4d. NH4+
e. H2O
2HSO3
C2H3O2
HAsO4
NH3
OH5. Give the conjugate acid of the following
a. C7H5O2b. BrO2c. NH3
d. H2AsO4e. CO32HC7H5O2
HBrO2
NH4+
H3AsO4
HCO36. Identify the Bronsted-Lowry acid and the Bronsted-Lowry base in each reaction and the conjugate acid/base pair
a. NH4+ + CN-  HCN + NH3
acid
base
conjugate base conjugate acid
b. (CH3)3N + H2O  (CH3)3NH+ + OHbase
c. HCHO2 +
acid
acid
conjugate acid conjugate base
PO43- 
CHO2- + HPO42-
base
conjugate base conjugate acid
7. a. HC2O4- 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.
HC2O4- + H2O  H2C2O4 + OHHC2O4- + H2O  C2O42-+ H3O+
b. What is the conjugate acid of HC2O4- ? What is the conjugate base?
H2C2O4; C2O428. For each of the following reactions, identify the Lewis acid and the Lewis base
a. 4NH3 + Zn2+  [Zn(NH3)4]2+
base acid
b. 2Cl- + BeCl2  [BeCl4]2base acid
c. Mg2+ + 6H2O  [Mg(H2O)6]2+
acid base
9. Which of the following could not act as a ligand in a complex ion of a transition metal?
a. Clb. NCl3
c. PCl3
d. CH4
10. Prepare a table in which you compare the definitions of acids and bases according to the Lewis, Bronsted-Lowry,
and Arrhenius theories. Which is the most general; that is, which includes the others within its scope? Explain.
acid
bases
+
Arrhenius
produces H in water
produces OH- in water
Bronsted-Lowry
proton donor
proton acceptor
Lewis
electron pair acceptor
electron pair donor
Lewis is the most general
11. What color is litmus in an acid? In a base?
Red; blue
12. What color is phenolphthalein in an acid? In a base? Clear; pink
13. Write equations for the following reactions
a. sulfuric acid + copper(II) oxide
H2SO4 + CuO  CuSO4 + H2O
b. nitric acid + sodium hydrogen carbonate
HNO3 + NaHCO3  NaNO3 + H2O + CO2
c. phosphoric acid + potassium hydroxide
H3PO4 + 3KOH  K3PO4 + 3H2O
d. ethanoic acid + aluminum
6CH3COOH + 2Al  2Al(CH3OO)3 + 3H2
e. hydrochloric acid + calcium hydroxide
2HCl + Ca(OH)2  CaCl2 + 2H2O
f. hydrobromic acid + magnesium carbonate
2HBr + MgCO3  MgBr2 + CO2 + H2O
14. What are some properties of acids? Taste sour, turns red in litmus
15. What are some properties of bases? Taste bitter, turns blue in litmus, slippery
16. 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
17. Name each of the following and label them as a weak/strong acid or weak/strong base
a. H3PO4
b. Ca(OH)2
c. Al(OH)3
d. HNO3
e. NH3
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
18. Which of the following solutions will be the poorest conductor of electricity?
a. HCl
b. CH3COOH
c. NaOH
d. NaCl
19. Which of the following has the highest concentration of [H+]? 0.1 mol dm-3 HCl or 0.1 mol dm-3 HF
20. What is the [H+] in each?
a. 0.5 mol dm-3 HCl
b. 0.002 mol dm-3 HNO3
-3
0.5 mol dm
0.002 mol dm-3
21. What is the [OH ] in each?
b. 0.03 mol dm-3 Ca(OH)2
b. 0.5 mol dm-3 NaOH
-3
0.5 mol dm
0.06 mol dm-3
22. What is the pH of a 0.0034 M HNO3 solution?
2.5
23. 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
24. Which of the following solutions would have the lowest pH?
0.10 M HCl, 0.009 M HNO3, 0.340 M HBr
25. 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
+
26. 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
-6
1 x 10 , acidic
4 x 10 -9 , basic
1 x 10 -2, acidic
d. pOH = 5
e. pH = 3.4
f. pOH = 4.2
1 x 10 -9, basic
4.0 x 10 -4, acidic
1.6 x 10 -10, basic
27. Determine the pH of the following solutions (label if they are acidic or basic)
b. [H+] = 2.3 x 10 -3
c. [OH-] = 1.0 x 10 -11
a. [H+] = 1.0 x 10 -12
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
b. 0.001 mol dm-3 HI 3; acidic
e. 1 x 10 -2 mol dm-3 HNO3
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
28. Which of the solutions in the previous problem is the most acidic? Most basic?
E; h
29. Which of the solutions in #27 has the highest hydronium ion concentration? Highest hydroxide ion
concentration?
E; h
30. 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
-10
-12
1 x 10 M
1 x 10 M
0.003 M
Review
31. Write a balanced reaction when magnesium metal reacts with hydrobromic acid
Mg + 2HBr  MgBr2 + H2
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
3HNO3 + Al(OH)3  3H2O + Al(NO3)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. H2O
Bent
Polar
Hydrogen bond and LD
b. NH3
c. CH4
trigonal pyramidal
tetrahedral
polar
nonpolar
hydrogen bond and LD
London dispersion
CH4 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. H2 + F2 <-> 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