Page path
• CHEM101_MH_V4
• Topic 13: Acids and Bases
Started on Friday, April 15, 2022, 8:48 PM
State Finished
Completed on Friday, April 15,
... [Show More] 2022, 9:08 PM
Time taken 19 mins 14 secs
Grade 115.00 out of 115.00 (100%)
Question 1
Correct
4.60 points out of 4.60
Flag question
Question text
A solution of chloroform, CHCl3, and acetone, (CH3)2CO, exhibits a negative deviation from Raoult's law. This result implies that
Select one:
a. chloroform-chloroform interactions are stronger than chloroform-acetone interactions.
b. chloroform-chloroform interactions are weaker than chloroform-acetone interactions.
c. acetone-acetone interactions are stronger than chloroform-acetone interactions.
d. acetone-acetone interactions are weaker than chloroform-acetone interactions.
e. Choice 2 and 4
Question 2
Correct
4.60 points out of 4.60
Flag question
Question text
At 10°C one volume of water dissolves 3.10 volumes of chlorine gas at 1.00 atm pressure. What is the Henry's law constant of Cl2 in water?
(R = 0.0821 atm • L • mol–1• K–1 )
Select one:
a. 3.8 mol • L–1• atm–1
b. 0.043 mol • L–1• atm–1
c. 36 mol • L–1• atm–1
d. 3.1 mol • L–1• atm–1
e. 0.13 mol • L–1• atm–1
Question 3
Correct
4.60 points out of 4.60
Flag question
Question text
What is the vapor pressure above a solution prepared by dissolving 0.500 mol of a nonvolatile solute in 275 g of hexane (86.18 g/mol) at 49.6°C? P°hexane = 400.0 torr at 49.6°C.
Select one:
a. 54 torr
b. 154 torr
c. 246 torr
d. 346 torr
e. 400. torr
Question 4
Correct
4.60 points out of 4.60
Flag question
Question text
A solution is 40.00% by volume benzene (C6H6) in carbon tetrachloride at 20°C. The vapor pressure of pure benzene at this temperature is 74.61 mmHg and its density is 0.87865 g/cm3; the vapor pressure of pure carbon tetrachloride is 91.32 mmHg and its density is 1.5940 g/cm3. If this solution is ideal, its total vapor pressure at 20°C is
Select one:
a. 84.64 mmHg
b. 84.30 mmHg
c. 82.96 mmHg
d. 81.63 mmHg
e. 165.93 mmHg
Question 5
Correct
4.60 points out of 4.60
Flag question
Question text
Safrole was once used as a flavoring in root beer, until it was banned in 1960. What is the vapor pressure of a solution prepared by dissolving 0.75 mol of nonvolatile safrole in 950 g of ethanol (46.07 g/mol)? P°ethanol = 50.0 torr at 25°C.
Select one:
a. 1.8 torr
b. 11 torr
c. 15 torr
d. 40 torr
e. 48 torr
Question 6
Correct
4.60 points out of 4.60
Flag question
Question text
Which combination of a 36.0% (w/w) stock solution of acetic acid (d = 1.045 g/mL) and water will result in 1.00 kg of a 15.0% (w/w) acetic acid solution?
Select one:
a. 417 mL of 36% acetic acid in 583 mL of distilled water
b. 417 g of 36% acetic acid in 583 g of distilled water
c. 360 mL of 36% acetic acid in 640 mL of distilled water
d. 360 g of 36% acetic acid in 640 g of distilled water
e. 150 g of 36% acetic acid in 850 g of distilled water
Question 7
Correct
4.60 points out of 4.60
Flag question
Question text
What is the name of a solution that obeys Raoult's law?
Select one:
a. Ideal solution
b. Nonideal solution
c. Suspension
d. Solute
e. Solvent
Question 8
Correct
4.60 points out of 4.60
Flag question
Question text
The osmotic pressure of a 0.82 M HCl solution is 35.9 atm at 18°C. Calculate the van't Hoff factor for HCl at this concentration.
Select one:
a. 1.8
b. 17.2
c. 1.5
d. 2.00
Question 9
Correct
4.60 points out of 4.60
Flag question
Question text
Which is most soluble in CCl4?
Select one:
a. NaCl
b. H2O
c. NaOH
d. C8H18
e. CH3OH
Question 10
Correct
4.60 points out of 4.60
Flag question
Question text
Cadmium bromide is used in photography and lithography. What is the molality of a solution prepared by dissolving 45.38 g of CdBr2 in 375.0 g of water?
Select one:
a. 0.03035 m
b. 0.01600 m
c. 0.1210 m
d. 0.4446 m
e. 16.00 m
Question 11
Correct
4.60 points out of 4.60
Flag question
Question text
What mass of LiOH is required to prepare 0.250 L of a 3.55 M solution?
Select one:
a. 0.0371 g
b. 0.888 g
c. 21.3 g
d. 250. g
e. 340. g
Question 12
Correct
4.60 points out of 4.60
Flag question
Question text
The structure of Vitamin B1, thiamine, is shown here. Vitamin B1 is most soluble in _________.
Select one:
a. fats
b. water
c. air
d. carbon tetrachloride
e. octane
Question 13
Correct
4.60 points out of 4.60
Flag question
Question text
The distinguishing characteristic of all electrolyte solutions is that they
Select one:
a. contain molecules.
b. conduct electricity.
c. react with other solutions.
d. always contain acids.
e. conduct heat.
Question 14
Correct
4.60 points out of 4.60
Flag question
Question text
A 0.100 m K2SO4 solution has a freezing point of –0.43°C. What is the van't Hoff factor for this solution?
(Kf = 1.86°C/m)
Select one:
a. 0.77
b. 1.0
c. 2.3
d. 3.0
e. 3.7
Question 15
Correct
4.60 points out of 4.60
Flag question
Question text
Since arsenic is a nonmetal, As2O3 is expected to be a/an _____ oxide.
Select one:
a. acidic
b. ionic
c. amphoteric
d. neutral
e. basic
Question 16
Correct
4.60 points out of 4.60
Flag question
Question text
Ammonium chloride is used as an electrolyte in dry cells. Which statement about a 0.10 M solution of NH4Cl is correct?
Select one:
a. The solution is weakly basic.
b. The solution is strongly basic.
c. The solution is neutral.
d. The solution is acidic.
e. The values for Ka and Kb for the species in solution must be known before a prediction can be made.
Question 17
Correct
4.60 points out of 4.60
Flag question
Question text
Which is a Lewis acid?
Select one:
a. CH3NH2
b. BCl3
c. F–
d. BF4–
e. CH4
Question 18
Correct
4.60 points out of 4.60
Flag question
Question text
What is the pH of a 0.014 M Ca(OH)2 solution?
Select one:
a. 1.85
b. 1.55
c. 12.15
d. 12.45
e. 15.85
Question 19
Correct
4.60 points out of 4.60
Flag question
Question text
What is the name given to a substance that can act as a Brønsted acid or as a Brønsted base according to what it is reacting with?
Select one:
a. hydrophilic
b. hydrophobic
c. amphoteric
d. isoprotic
e. isoelectronic
Question 20
Correct
4.60 points out of 4.60
Flag question
Question text
What is the conjugate base of water?
Select one:
a. H3O+
b. OH–
c. H3O
d. OH
e. H2O2
Question 21
Correct
4.60 points out of 4.60
Flag question
Question text
Calculate the pH of a 0.021 M NaCN solution. [Ka(HCN) = 4.9 × 10–10]
Select one:
a. 1.68
b. 3.19
c. 4.69
d. 9.31
e. 10.81
Question 22
Correct
4.60 points out of 4.60
Flag question
Question text
Which is a Lewis acid but not a Brønsted acid?
Select one:
a. HCN
b. CO32–
c. OH–
d. Cl–
e. Al3+
Question 23
Correct
4.60 points out of 4.60
Flag question
Question text
What is the pH of a 0.056 M HNO3 solution?
Select one:
a. 0.056
b. 1.25
c. 12.75
d. 2.88
e. 11.11
Question 24
Correct
4.60 points out of 4.60
Flag question
Question text
Below is a representation of an aqueous solution of a weak acid HA at equilibrium. (Each circle represents 1.0 mmol of atoms, and the volume of the box is 1.0 L. Solvent water molecules are not shown for clarity.)
What is the percent ionization of HA?
Select one:
a. 100%
b. 50%
c. 25%
d. 12.5%
e. Cannot be calculated without knowledge of Ka
Question 25
Correct
4.60 points out of 4.60
Flag question
Question text
Hard water deposits (calcium carbonate) have built up around your bathroom sink. Which of these substances would be most effective in dissolving the deposits?
Select one:
a. ammonia
b. bleach (sodium hypochlorite)
c. lye (sodium hydroxide)
d. vinegar (acetic acid) [Show Less]