chapter 4-7

1. Let’s Get Started
• Get in equal groups (let’s shoot for 7-8 people
each)
• Pull out a paper and write down the names of
the people in your group.
• Turn on gaming buzzer by holding the on/off
button for 5 seconds

2. Name 3 factors that influences
reaction rate.

3. Answer:
Temperature, concentration, catalyst,
activation energy, nature of the
reactants, molecular collisions

4. Which of the following will have the
lowest freezing point?
0.1 M NaCl
0.1 M BaCl2
0.1 M AlCl3

5. Answer
0.1 M AlCl3

6. In an aqueous solution of KCl, what
is water called?

7. Answer
solvent

8. What is stronger ionic bonds or
hydrogen bonds?

9. Answer
Ionic bond

10. Is the following reaction exothermic
or endothermic?
2SO2 + O2  2SO3 + heat

11. Answer
exothermic

12. Molecules in a solid phase have
higher or lower kinetic energy
compared with liquid and gases?

13. Answer
Lower

14. What typically increases the
solubility of a solute in a solvent?
(Not gases)

15. Answer
Temperature
Solubility is a physical property and is a
given amount of solute than can
dissolve in a given amount of solvent

16. Balance the following reaction:
CO2 + H2O  C6H12O6 + O2

17. Answer
6CO2 + 6H2O  C6H12O6 + 6O2

18. For the reaction:
4Fe + 3O2  2Fe2O3
Is Fe oxidized or reduced?

19. Answer
Oxidized

20. What are the two definitions of
reduction?

21. Answer
1) Gain of electrons
2) Loss of oxygen and/or gain of
hydrogen

22. The number of molecules of
water (H2O) in 1 mole of water is

23. Answer
6.02 x 1023

24. Give the formula mass of NH3
(must have correct units).

25. Answer
17 amu

26. Weak attractions between
nonpolar molecules are called?

27. Answer
London Dispersion Forces

28. What is the molarity (M) of a 800 ml
solution that contains 72 g of
hydrochloric acid (HCl)?

29. Answer
72 g HCl x 1 mole HCl = 2 moles
36 g HCl
M = moles/L
=2 moles/0.8 L = 2.5 M

30. Which of the following will engage in
hydrogen bonding?
a) H2O
b) CH3OH
c) NH3
d) CH3
e) HCl
f) CH3NH2
g) CH2CH2

31. Answer
H2O
CH3OH
NH3
CH3NH2

32. Water is likely to be a poor
solvent for which types of
molecules?

33. Answer
Nonpolar molecules

34. A 6 Liter water sample contains 3 μg
of mercury. What is the
concentration of mercury in ppm
and ppb?

35. Answer
ppb = ug/kg (L) = 3/6 = 0.5 ppb
ppm = mg /kg (L)
1000 ug = 1 mg so:
3 ug x 1 mg = 0.003 mg
1000 ug
ppm = 0.003/6 =0.0005 or 5 x 10-4 ppm

36. Consider the following reaction:
CH4 + 2O2  CO2 + 2H2O
How many grams of CO2 are
produced from 200 g of CH4?

37. Answer
200 g CH4 = 1 mole CH4 = 1 mole CO2 = 44 g CO2 = 550 g CO2
16 g CH4 1 mole CH4 1 mole CO2

38. What is the osmolarity of a 3M
solution of AlCl3?

39. Answer
Osmol = M x i = 3 x 4 = 12

40. What is the definition of a strong
electrolyte?

41. Answer
-Dissociates completely to ions in
water
-conducts electricity

42. What is the small amount of
energy required to initiate a
chemical reaction called?

43. Answer
Activation energy

44. What is chemical equilibrium?

45. Answer
When the rate of forward reaction is
equal to the rate of the reverse
reaction

46. If the following reaction is at
equilibrium, which direction will the
reaction proceed if you:
add more I2
remove HI
remove H2
increase the temperature
H2 + I2  2HI + heat

47. Answer
add more I2 = to the right or towards products
remove HI = to the right or toward products
remove H2 = to the left or toward reactant
increase the temperature = to the left or toward reactants

48. The formation of NH3 from N2 and
H2 has an equilibrium constant of
3.5 x 108.
Is this reaction product or
reactant favored?
N2 + 3H2  2NH3

49. Answer
Product favored

50. If 35 g of KBr is dissolved in 250 ml,
what is the percent w/v of the
solution?

51. Answer
Weight/volume (w/v)% = weight solute x 100
volume of solution
=35/250 x 100 = 14%

52. A sample of gas at 350 K and 1.33
atm occupies a volume of 50L. How
many moles of the gas are present?
R = 0.0821 Latm/molK

53. Answer
PV= nRT
(1.33)(50)= n(0.0821)(350)
n= 2.3 moles

54. What is the equilibrium
expression for the following
reaction?
2SO2 + O2  2SO3

55. Answer
K = [SO3]2
[SO2]2[O2]

56. A substance that increases a
reaction rate but is not consumed by
the reaction is
called a(n)?

57. Answer
Catalyst

58. If the pressure is increase on the
following system at equilibrium.
Which way will the reaction
proceed?
N2 + 3H2  2NH3

59. Answer
Towards the size with fewer moles
To the right

60. If “A” contains 20% NaCl and is
separated by a semipermeable
membrane from “B” which contains
10% AgBr, which way will water
flow?

61. Answer
Osmosis is the movement of solvent from
region of lower solute concentration to
higher solute concentration
-Water will flow toward A

62. What volume of a 12.0 M HCl
must be used to make 4.0 L of a
6.0 M HCl?

63. Answer
M1V1 = M2V2
(12)(V1) = (6)(4)
V1 = 2 L

64. In the following reaction, what is the
species that is being reduced?
Zn+2 + 2Al  3Zn + Al+3

65. Answer
Zn2+

66. hydrogen gas at elevated
temperatures to form methanol
according to this equation:
CO + 2H2  CH3OH
At equilibrium there is 0.40 M of CO,
0.30 M of H2, and 0.06 M of CH3OH.
What is the value of K?

67. Answer
K = [CH3OH]
[CO][H2]2
= [0.06]
[0.4][0.3]2
= 1.7

68. Study energy diagrams