Question 1

Solutions that have identical osmotic pressures are called __________ solutions.

Accepted Answer

Isotonic solutions have identical osmotic pressures, meaning that the concentration of solutes in the solution is equal to the concentration of solutes inside the cell. This results in no net movement of water across the cell membrane and is important for maintaining cellular homeostasis. Hypertonic solutions have a higher concentration of solutes and cause water to move out of the cell, while hypotonic solutions have a lower concentration of solutes and cause water to move into the cell. Hemolytic and dialytic are not related to osmotic pressure of solutions.

Question 2

A 5.05-gram sample of a compound is dissolved in enough water to form 100.0 mL of solution.This solution has an osmotic pressure of 25.0 torr at 25°C.If it is assumed that each molecule of the solute dissociates into two particles (in this solvent),what is the molar mass of this solute?

Accepted Answer

The answer of A 5.05-gram sample of a compound is...

Question 3

What is reverse osmosis?

Accepted Answer

Reverse osmosis involves applying a pressure greater than the osmotic pressure to a concentrated solution, causing the solvent to flow from the concentrated solution to the dilute solution, effectively purifying the solvent by removing solutes.

Question 4

The vapor pressure of water at 90°C is 0.692 atm.What is the vapor pressure (in atm)of a solution made by dissolving 4.13 mole(s)of CsF(s)in 1.00 kg of water? Assume that Raoult's law applies.

Accepted Answer

The answer of The vapor pressure of water at 90°C...

Question 5

Which of the following solutions has the lowest boiling point?

Accepted Answer

The boiling point elevation depends on the number of solute particles in the solution. C₂H₆O₂ is a non-electrolyte and does not dissociate into ions, so it contributes fewer particles compared to the ionic compounds which dissociate into multiple ions. Thus, it has the lowest boiling point elevation effect.

Question 6

Calculate the osmotic pressure (in torr)of 6.00 L of an aqueous 0.958 M solution at 30.°C,if the solute concerned is totally ionized into three ions (e.g. ,it could be Na₂SO₄ or MgCl₂).

Accepted Answer

The answer of Calculate the osmotic pressure (in torr)of 6.00...

Question 7

Consider pure water separated from an aqueous sugar solution by a semipermeable membrane,which allows water to pass freely but not sugar.After some time has passed,the concentration of sugar solution:

Accepted Answer

The process that occurs in this scenario is osmosis. As pure water passes through the semipermeable membrane into the sugar solution, the concentration of water on the side with the sugar solution decreases. As a result, the concentration of sugar in the solution will become more concentrated, leading to an increase in the concentration of sugar on that side. Therefore, choice B, which states that the concentration of sugar solution will decrease, is the correct answer.

Question 8

In osmosis:

Accepted Answer

Osmotic pressure is directly proportional to the concentration of the solute and inversely proportional to the molar mass of the solute. Therefore, if the osmotic pressure is known, it can help determine the molar mass of the solute using the equation: π = MRT, where π is the osmotic pressure, M is the molarity of the solution, R is the gas constant, and T is the temperature in Kelvin.

B, C, and D are incorrect statements. The semipermeable membrane is used to selectively allow the passage of solvent molecules and restrict the passage of solute molecules, and it does not affect the freezing or melting points of a solution. Solutions can have identical osmotic pressures if they have the same concentration of solute and temperature. Temperature affects the osmotic pressure because it affects the rate of diffusion of the solvent molecules through the membrane.

Question 9

What type of colloid is formed when a gas is dispersed in a liquid?

Accepted Answer

A gas dispersed in a liquid forms a foam, which is a type of colloid.

Question 10

You have a 10.40-g mixture of table sugar (C₁₂H₂₂O₁₁)and table salt (NaCl).When this mixture is dissolved in 150.g of water,the freezing point is found to be -2.24°C.Calculate the percent by mass of sugar in the original mixture.

Accepted Answer

The answer of You have a 10.40-g mixture of table...

Question 11

The most likely reason for colloidal dispersion is __________.

Accepted Answer

Colloidal dispersion is maintained by the electrostatic repulsion between the colloidal particles, which prevents them from coagulating or precipitating. The Tyndall effect and emulsion formation are properties or characteristics of colloidal dispersions. However, coagulation and precipitation disrupt the dispersion and result in the formation of larger particles that settle down, which is not the desired outcome for a colloidal dispersion.

Question 12

Determine the osmotic pressure of a solution that contains 0.048 g of a hydrocarbon solute (molar mass = 340 g/mol)dissolved in benzene to make a 350-mL solution.The temperature is 20.0°C.

Accepted Answer

The correct answer is D because the osmotic pressure is 7.4 torr.

Question 13

A 0.20 M solution of MgSO₄ has an observed osmotic pressure of 7.6 atm at 25°C.Determine the observed van't Hoff factor for this experiment.

Accepted Answer

We can use the formula:

Π = iMRT

where Π is the observed osmotic pressure, M is the molarity of the solution, R is the gas constant, and T is the temperature in kelvin.

We can rearrange this formula to solve for i:

i = Π / MRT

Plugging in the values given:

i = (7.6 atm) / (0.20 mol/L * 0.08206 L*atm/mol/K * 298 K)

i = 1.6

Therefore, the observed van't Hoff factor is 1.6.

The other answer choices are: 
A) 19 - This is an unrealistic value for the van't Hoff factor and is likely a calculation error. 
B) 0.31 - This is not a valid value for the van't Hoff factor as it cannot be less than 1. 
D) 1.8 - This is not the correct answer as the calculation yields a value of 1.6, not 1.8.
E) 2.0 - This is not a valid value for the van't Hoff factor as it cannot be greater than the total number of particles in solution (which is 3 for MgSO4).

Question 14

The osmotic pressure of a 0.0100 M solution of NaCl in water at 25°C is found to be different from 372 torr because:

Accepted Answer

The answer of The osmotic pressure of a 0.0100 M...

Question 15

What type of colloid is formed when a liquid is dispersed in a gas?

Accepted Answer

When a liquid is dispersed in a gas, it forms an aerosol colloid. This type of colloid is made up of small droplets of liquid suspended in a gas medium. Examples of aerosols include fog, smoke, and mist.

Question 16

Calculate the molarity of a solution containing KCl and water whose osmotic pressure at 21.6°C is 125 torr.Assume complete dissociation of the salt.

Accepted Answer

The answer of Calculate the molarity of a solution containing...

Question 17

Which of the following solutions would have the highest osmotic pressure?

Accepted Answer

MgBr2 (magnesium bromide) dissociates into three ions (Mg^2+ and 2 Br^-), which increases the number of particles in solution, thereby increasing the osmotic pressure compared to the other options which either do not dissociate into as many particles or do not dissociate at all.

Question 18

What is the freezing point of an aqueous 1.58 molal NaCl solution? (K_f = 1.86°C/m)

Accepted Answer

The freezing point depression depends on the molality of the solution and the molal freezing point depression constant (K_f) which is given as 1.86°C/m. △Tf = K_f x molality Substituting the given values, we get: △Tf = 1.58 mol/kg x 1.86°C/m △Tf = 2.94°C Since the freezing point is lowered by this amount, the freezing point of the solution would be the normal freezing point minus the △Tf, which is: Freezing point of water = 0°C Freezing point of the solution = 0°C - 2.94°C = -5.88°C Therefore, the freezing point of the aqueous 1.58 molal NaCl solution is -5.88°C. The correct answer is option C.

Question 19

What is the expected boiling point of a solution prepared by dissolving 7.27 g of sodium iodide (NaI)in 68.6 g of water (H₂O)? For water,T_b = 100.00^oC and K_b = 0.512^oC m^-¹.

Accepted Answer

The answer of What is the expected boiling point of...

Question 20

The observed van't Hoff factor for an electrolyte is less than the expected factor because of __________.

Accepted Answer

The observed van't Hoff factor for an electrolyte is less than the expected factor because of ion pairing, which occurs when ions associate with each other in solution rather than remaining fully dissociated. This decreases the effective concentration of ions in solution and results in a lower observed van't Hoff factor.

Quiz 11: Properties of Solutions

Solutions that have identical osmotic pressures are called __________ solutions.

A 5.05-gram sample of a compound is dissolved in enough water to form 100.0 mL of solution.This solution has an osmotic pressure of 25.0 torr at 25°C.If it is assumed that each molecule of the solute dissociates into two particles (in this solvent) ,what is the molar mass of this solute?

What is reverse osmosis?

The vapor pressure of water at 90°C is 0.692 atm.What is the vapor pressure (in atm) of a solution made by dissolving 4.13 mole(s) of CsF(s) in 1.00 kg of water? Assume that Raoult's law applies.

Which of the following solutions has the lowest boiling point?

Calculate the osmotic pressure (in torr) of 6.00 L of an aqueous 0.958 M solution at 30.°C,if the solute concerned is totally ionized into three ions (e.g. ,it could be Na₂SO₄ or MgCl₂) .

Consider pure water separated from an aqueous sugar solution by a semipermeable membrane,which allows water to pass freely but not sugar.After some time has passed,the concentration of sugar solution:

In osmosis:

What type of colloid is formed when a gas is dispersed in a liquid?

You have a 10.40-g mixture of table sugar (C₁₂H₂₂O₁₁) and table salt (NaCl) .When this mixture is dissolved in 150.g of water,the freezing point is found to be -2.24°C.Calculate the percent by mass of sugar in the original mixture.

The most likely reason for colloidal dispersion is __________.

Determine the osmotic pressure of a solution that contains 0.048 g of a hydrocarbon solute (molar mass = 340 g/mol) dissolved in benzene to make a 350-mL solution.The temperature is 20.0°C.

A 0.20 M solution of MgSO₄ has an observed osmotic pressure of 7.6 atm at 25°C.Determine the observed van't Hoff factor for this experiment.

The osmotic pressure of a 0.0100 M solution of NaCl in water at 25°C is found to be different from 372 torr because:

What type of colloid is formed when a liquid is dispersed in a gas?

Calculate the molarity of a solution containing KCl and water whose osmotic pressure at 21.6°C is 125 torr.Assume complete dissociation of the salt.

Which of the following solutions would have the highest osmotic pressure?

What is the freezing point of an aqueous 1.58 molal NaCl solution? (K_f = 1.86°C/m)

What is the expected boiling point of a solution prepared by dissolving 7.27 g of sodium iodide (NaI) in 68.6 g of water (H₂O) ? For water,T_b = 100.00^oC and K_b = 0.512^oC m^-¹.

The observed van't Hoff factor for an electrolyte is less than the expected factor because of __________.

Quiz 11: Properties of Solutions

Solutions that have identical osmotic pressures are called __________ solutions.

A 5.05-gram sample of a compound is dissolved in enough water to form 100.0 mL of solution.This solution has an osmotic pressure of 25.0 torr at 25°C.If it is assumed that each molecule of the solute dissociates into two particles (in this solvent) ,what is the molar mass of this solute?

What is reverse osmosis?

The vapor pressure of water at 90°C is 0.692 atm.What is the vapor pressure (in atm) of a solution made by dissolving 4.13 mole(s) of CsF(s) in 1.00 kg of water? Assume that Raoult's law applies.

Which of the following solutions has the lowest boiling point?

Calculate the osmotic pressure (in torr) of 6.00 L of an aqueous 0.958 M solution at 30.°C,if the solute concerned is totally ionized into three ions (e.g. ,it could be Na2SO4 or MgCl2) .

Consider pure water separated from an aqueous sugar solution by a semipermeable membrane,which allows water to pass freely but not sugar.After some time has passed,the concentration of sugar solution:

In osmosis:

What type of colloid is formed when a gas is dispersed in a liquid?

You have a 10.40-g mixture of table sugar (C12H22O11) and table salt (NaCl) .When this mixture is dissolved in 150.g of water,the freezing point is found to be -2.24°C.Calculate the percent by mass of sugar in the original mixture.

The most likely reason for colloidal dispersion is __________.

Determine the osmotic pressure of a solution that contains 0.048 g of a hydrocarbon solute (molar mass = 340 g/mol) dissolved in benzene to make a 350-mL solution.The temperature is 20.0°C.

A 0.20 M solution of MgSO4 has an observed osmotic pressure of 7.6 atm at 25°C.Determine the observed van't Hoff factor for this experiment.

The osmotic pressure of a 0.0100 M solution of NaCl in water at 25°C is found to be different from 372 torr because:

What type of colloid is formed when a liquid is dispersed in a gas?

Calculate the molarity of a solution containing KCl and water whose osmotic pressure at 21.6°C is 125 torr.Assume complete dissociation of the salt.

Which of the following solutions would have the highest osmotic pressure?

What is the freezing point of an aqueous 1.58 molal NaCl solution? (Kf = 1.86°C/m)

What is the expected boiling point of a solution prepared by dissolving 7.27 g of sodium iodide (NaI) in 68.6 g of water (H2O) ? For water,Tb = 100.00oC and Kb = 0.512oC m-1.

The observed van't Hoff factor for an electrolyte is less than the expected factor because of __________.

Calculate the osmotic pressure (in torr) of 6.00 L of an aqueous 0.958 M solution at 30.°C,if the solute concerned is totally ionized into three ions (e.g. ,it could be Na₂SO₄ or MgCl₂) .

You have a 10.40-g mixture of table sugar (C₁₂H₂₂O₁₁) and table salt (NaCl) .When this mixture is dissolved in 150.g of water,the freezing point is found to be -2.24°C.Calculate the percent by mass of sugar in the original mixture.

A 0.20 M solution of MgSO₄ has an observed osmotic pressure of 7.6 atm at 25°C.Determine the observed van't Hoff factor for this experiment.

What is the freezing point of an aqueous 1.58 molal NaCl solution? (K_f = 1.86°C/m)

What is the expected boiling point of a solution prepared by dissolving 7.27 g of sodium iodide (NaI) in 68.6 g of water (H₂O) ? For water,T_b = 100.00^oC and K_b = 0.512^oC m^-¹.