Question 1

What volume of ethyl alcohol is contained in 35 mL (1 oz. )of 86 proof liquor,which is 43% (v/v)alcohol?
A) 30 mL
B) 43 mL
C) 15 mL
D) 37 mL

Accepted Answer

To find the volume of ethyl alcohol in 35 mL of 86 proof liquor, we need to use the formula:

Volume of ethyl alcohol = (proof/2) x volume of solution

Here, the proof is 86 and the volume of solution is 35 mL. Substituting the values, we get:

Volume of ethyl alcohol = (86/2) x 35/100
                       = 43 x 0.35
                       = 15.05 mL

Therefore, the answer is C) 15 mL since we need to round off the result to the nearest mL.

Question 2

How many mL of 6.00 M HCl are needed to prepare 1500 mL of 0.200 M HCl solution? A) 1.80 * 10⁴ B) 125 C) 2.00 *10^-3 D) 50.0

Accepted Answer

To prepare a solution with a lower concentration from a solution with a higher concentration, use the dilution equation:M1V1 = M2V2(6.00 M)(V1) = (0.200 M)(1500 mL)V1 = 50.0 mL

Question 3

The boiling point of a solution of sugar water is
A) higher than that of pure solvent.
B) the same as that of pure solvent.
C) lower than that of pure solvent.
D) impossible to determine.

Accepted Answer

Adding sugar to water increases the boiling point of the solution compared to the pure solvent due to the colligative property known as boiling point elevation.

Question 4

What is the underlying process involved in dialysis?
A) mixtures are homogenous.
B) osmosis is due to a difference in solution concentrations.
C) pressure is applied to the blood squeezing out the impurities.
D) an electrical potential separates the blood from the impurities.

Accepted Answer

Dialysis involves the process of osmosis, in which solutes and water move from an area of higher concentration to an area of lower concentration. In this case, impurities and excess waste products are removed from the blood by passing it through a semi-permeable membrane and into a solution with a lower concentration of these substances.

Question 5

What is the osmotic pressure of a 0.050 M solution of AlCl₃ in water that is at 0.00S1U1P1$\circ$S1S1P0C? Consider AlCl₃ to be a strong electrolyte. A) 8.5 * 10² torr B) 1.1 atm C) 2.2 atm D) 3.4 * 10³ torr

Accepted Answer

The osmotic pressure can be calculated using the formula π = MRT, where M is the molarity of the solution, R is the gas constant, and T is the temperature in Kelvin. Converting 0.00°C to Kelvin gives 273 K. Therefore:

π = (0.050 M)(0.0821 L*atm/(mol*K))(273 K) = 1.13 atm

Converting atm to torr gives:

π = 1.13 atm * 760 torr/atm = 856.8 torr

Rounding to three significant figures gives the answer of 3.4×10^10 torr, which is choice D.

Question 6

Which of the following tend to stabilize colloids and prevent suspended particles from settling?
A) presence of emulsifying agents
B) absorption of charges by colloid particles
C) absence of ionic salts
D) more than one response is correct

Accepted Answer

Both presence of emulsifying agents and absorption of charges by colloid particles tend to stabilize colloids and prevent suspended particles from settling. Therefore, both A and B are correct. Absence of ionic salts may also contribute to stability in some cases, but it is not always necessary, so C is not a correct answer.

Question 7

An isotonic salt solution is 0.90% (w/w)NaCl in water.How many grams of NaCl are contained in 1.00 kg of such a solution?
A) 0.090
B) 0.90
C) 9.0
D) 90

Accepted Answer

An isotonic salt solution that is 0.90% (w/w) NaCl means that there are 0.90 grams of NaCl in every 100 grams of solution. Therefore, in 1.00 kg (or 1000 grams) of solution, there would be 9.0 grams of NaCl.

Question 8

Calculate the number of moles of ZnCl,in 100 mL of 0.300 M solution. A) 3.00 *10^-2 B) 0.300 C) 30.0 D) 3.00

Accepted Answer

To calculate the number of moles of ZnCl2 in the given solution, we first need to use the formula:

Molarity (M) = moles of solute / liters of solution

We are given the volume of the solution as 100 mL or 0.1 L, and the molarity as 0.300 M. Therefore,

0.300 M = moles of ZnCl2 / 0.1 L

Solving for moles of ZnCl2, we get:

moles of ZnCl2 = 0.300 M x 0.1 L = 0.030 moles

Therefore, the number of moles of ZnCl2 in 100 mL of 0.300 M solution is 0.030 moles or 3.00 x 10^-2 moles. So, the correct answer is A) 3.00.

Question 9

In the colloid known as mayonnaise,the dispersed phase is _____ .
A) a gas
B) a liquid
C) a solid
D) unknown

Accepted Answer

In mayonnaise, the dispersed phase is a liquid (oil) while the continuous phase is also liquid (vinegar or water). This makes it a type of emulsion, which is a type of colloid.

Question 10

Changes in boiling point,freezing point,and vapor pressure are A) the same for 2 M NaCl as they are for 2 M CaCl_2. B) the same for 50 mL of 2 M NaCl as they are for 250 mL of 1 M NaCl. C) the same for 75 mL of 2 M NaCl as they are for 50 mL of 2 M NaOH. D) the same at 1 atm as at 1.55 atm.

Accepted Answer

Changes in boiling point, freezing point, and vapor pressure depend on the concentration of solute particles in the solution. Therefore, the changes will not be the same for different solutes or different concentrations of the same solute.

Choice A is incorrect because NaCl and CaCl2 have different numbers of particles and will therefore have different changes in boiling point, freezing point, and vapor pressure at the same concentration.

Choice B is incorrect because the changes in boiling point, freezing point, and vapor pressure are dependent on the concentration of solute particles, not the volume of solution.

Choice D is incorrect because changes in boiling point, freezing point, and vapor pressure are dependent on the pressure of the surrounding environment. Therefore, changes at different pressures will not be the same.

Question 11

Two solutions with concentrations of 2% sugar and 4% sugar,respectively,are separated by a semipermeable membrane.During osmosis,there is a net flow of
A) sugar molecules from the concentrated to the dilute solution.
B) sugar molecules from the dilute to the concentrated solution.
C) water molecules from the concentrated to the dilute solution.
D) water molecules from the dilute to the concentrated solution.

Accepted Answer

During osmosis, water molecules move from an area of high concentration (less concentrated solution) to an area of low concentration (more concentrated solution) until both solutions have the same concentration. Therefore, the correct answer is D, water molecules move from the dilute (2% sugar) solution to the concentrated (4% sugar) solution.

Question 12

The spores from many molds produce an allergic reaction in many individuals.If mold spores in the air were to be considered a colloid,which technique would remove the spores best from a functioning air conditioner duct?
A) Place a filter made from woven fiberglass fibers in the duct.
B) Install an electrical device with both positive and negative poles.
C) Install an ultraviolet light producing device in the duct.
D) All of these responses work to the same extent.

Accepted Answer

The answer of The spores from many molds produce an...

Question 13

A solution is prepared by adding 25.0 mL of 1.30 M AlCl₃ solution to a flask,and then adding enough water to give a final volume of 200.0 mL.What is the molarity of the solution? A) 0.260 B) 0.163 C) 6.50 D) 1.24

Accepted Answer

To find the molarity, we need to use the equation M1V1 = M2V2 where M1 is the initial molarity, V1 is the initial volume, M2 is the final molarity, and V2 is the final volume. Plugging in the values we have, we get (1.30 M)(25.0 mL) = M2(200.0 mL), which solves to M2 = 0.163 M. Therefore, the answer is choice B.

Question 14

Compared to pure water,a salt water solution will have a
A) lower vapor pressure,freezing point and boiling point.
B) higher vapor pressure,freezing point and boiling point.
C) lower vapor pressure and freezing point and a higher boiling point.
D) higher freezing point and a lower vapor pressure and boiling point.

Accepted Answer

Adding salt to water lowers its vapor pressure and freezing point but raises its boiling point due to colligative properties.

Question 15

The rate of osmosis
A) can be increased by having larger pores in the membrane.
B) can be increased by removing the membrane.
C) can be increased by an increase in the atmospheric pressure.
D) cannot be increased by any of the responses.

Accepted Answer

The answer of The rate of osmosis
A) can be increased...

Question 16

A solution is prepared by dissolving 4.66 g of KCl in enough distilled water to give 250 mL of solution.KCl is a strong electrolyte.How will the freezing point of the solution be different from that of pure water? (Note: K_f for water is 1.86°C/M. ) A) solution will be 0.930°C lower than water B) solution will be 0.475°C lower than pure water C) solution will be 0.930°C higher than pure water D) solution will be 0.475°C higher than pure water

Accepted Answer

The answer of A solution is prepared by dissolving 4.66...

Question 17

The vapor pressure of a pure solvent is
A) higher than that of a solution.
B) impossible to determine.
C) the same as that of a solution.
D) lower than that of a solution.

Accepted Answer

The vapor pressure of a pure solvent is higher than that of a solution because the presence of a solute decreases the number of solvent molecules at the surface available to escape into the vapor phase, thus lowering the vapor pressure.

Question 18

Which of the following pairs correctly represent similar functions for a solution component and a colloid component?
A) solvent/dispersed phase
B) solute/dispersion medium
C) solvent/dispersion medium
D) more than one response is correct

Accepted Answer

Solvent and dispersion medium both serve as the continuous phase in their respective solutions/colloids.

Question 19

Which of the following pass through both osmotic and dialysis membranes?
A) solvent molecules
B) large molecules
C) cations
D) anions

Accepted Answer

Solvent molecules (such as water) can pass through both osmotic and dialysis membranes, while larger molecules, cations, and anions may not be able to pass through depending on their size and charge.

Question 20

A 0.9% NaCl (w/w)solution in water is
A) produced by mixing 0.9 moles of NaCl in a 100 moles of water.
B) produced and has the same final volume as a 0.9% solution in ethyl alcohol.
C) a solution that boils at or above 100S1U1P1$\circ$S1S1P0C.
D) All of these responses are correct.

Accepted Answer

A 0.9% NaCl solution in water is a saline solution that has a boiling point above 100°C due to the presence of dissolved salt, which elevates the boiling point.

Quiz 7: Solutions and Colloids

What volume of ethyl alcohol is contained in 35 mL (1 oz. ) of 86 proof liquor,which is 43% (v/v) alcohol?

How many mL of 6.00 M HCl are needed to prepare 1500 mL of 0.200 M HCl solution?

The boiling point of a solution of sugar water is

What is the underlying process involved in dialysis?

What is the osmotic pressure of a 0.050 M solution of AlCl₃ in water that is at 0.00^$\circ$C? Consider AlCl₃ to be a strong electrolyte.

Which of the following tend to stabilize colloids and prevent suspended particles from settling?

An isotonic salt solution is 0.90% (w/w) NaCl in water.How many grams of NaCl are contained in 1.00 kg of such a solution?

Calculate the number of moles of ZnCl,in 100 mL of 0.300 M solution.

In the colloid known as mayonnaise,the dispersed phase is _____ .

Changes in boiling point,freezing point,and vapor pressure are

Two solutions with concentrations of 2% sugar and 4% sugar,respectively,are separated by a semipermeable membrane.During osmosis,there is a net flow of

The spores from many molds produce an allergic reaction in many individuals.If mold spores in the air were to be considered a colloid,which technique would remove the spores best from a functioning air conditioner duct?

A solution is prepared by adding 25.0 mL of 1.30 M AlCl₃ solution to a flask,and then adding enough water to give a final volume of 200.0 mL.What is the molarity of the solution?

Compared to pure water,a salt water solution will have a

The rate of osmosis

A solution is prepared by dissolving 4.66 g of KCl in enough distilled water to give 250 mL of solution.KCl is a strong electrolyte.How will the freezing point of the solution be different from that of pure water? (Note: K_f for water is 1.86°C/M. )

The vapor pressure of a pure solvent is

Which of the following pairs correctly represent similar functions for a solution component and a colloid component?

Which of the following pass through both osmotic and dialysis membranes?

A 0.9% NaCl (w/w) solution in water is