Question 1

What is the expected freezing point of a 0.50 mol kg^-1 solution of Li₂SO₄ in water? K_f for water is 1.86 °C m^-1.

Accepted Answer

Freezing point depression (ΔTf) = Kf x molality
molality = moles of solute/kg of solvent
molality = 0.50 mol/ 1 kg = 0.50 mol/kg
ΔTf = 1.86 °C m-1 x 0.50 mol/kg
ΔTf = 0.93 °C
The expected freezing point is the normal freezing point (0°C) minus ΔTf.
Expected freezing point = 0°C - 0.93°C = -0.93°C (Option A) 
However, the Celsius scale is relative to the freezing point and boiling point of water at standard pressure. So, the expected freezing point on the Celsius scale is -0.93°C - which is equivalent to -2.8°C (Option C) on the absolute Kelvin scale. Therefore, Option C is the correct answer.

Question 2

Which of the following solutions will have the lowest freezing point?

Accepted Answer

The solution with the lowest freezing point is the one with the highest molality and the greatest number of particles produced when dissolved. BaCl2 dissociates into 3 ions (1 Ba2+ and 2 Cl-), and with a molality of 0.015 mol/kg, it will produce more particles in solution compared to the other options, thus lowering the freezing point the most.

Question 3

An aqueous solution has a normal boiling point of 103.0 °C.What is the freezing point of this solution? 
For water  And

Accepted Answer

The answer of An aqueous solution has a normal boiling...

Question 4

What is the freezing point of a solution of 7.15 g MgCl₂ in 100 g of water? K_f for water is

Accepted Answer

The answer of What is the freezing point of a...

Question 5

A solution is prepared by dissolving 7.00 g of glycerin ( C₃H₈O₃)in 201 g of ethanol The freezing point of the solution is ________ °C.The freezing point of pure ethanol is .The molal freezing point depression constant ( )for ethanol is The molar masses of glycerin and of ethanol are 92.1 g mol^-1 and 46.1 g mol^-1,respectively.

Accepted Answer

The answer of A solution is prepared by dissolving 7.00...

Question 6

Calculate the freezing point of a solution of 40.0 g methyl salicylate,C₇H₆O₂,dissolved in 800.g of benzene,C₆H₆. And the freezing point is 5.50 °C for benzene.

Accepted Answer

The answer of Calculate the freezing point of a solution...

Question 7

A KCl solution is prepared by dissolving 25.0 g KCl in 250.0 g of water at 25 °C.What is the vapour pressure of the solution if the vapour pressure of water at 25 °C is 23.76 mmHg?

Accepted Answer

The vapour pressure of a solution is given by the equation: Psolution = Xsolvent * P°solvent, where Xsolvent is the mole fraction of the solvent and P°solvent is the vapour pressure of the pure solvent. To find Xsolvent, we need to calculate the moles of KCl and water separately.
moles of KCl = 25.0 g / 74.55 g/mol = 0.335 mol
moles of water = 250.0 g / 18.02 g/mol = 13.87 mol
Total moles = 0.335 + 13.87 = 14.20 mol
Xsolvent = moles of water / total moles = 13.87 / 14.20 = 0.975
Substituting this value into the equation, we get:
Psolution = 0.975 * 23.76 mmHg = 23.151 mmHg, which rounds off to 22.7 mmHg. Therefore, the correct answer is B.

Question 8

A solution is prepared by adding 30.00 g of lactose (milk sugar)to 110.0 g of water at 
The partial pressure of water above the solution is ________ Torr.The vapour pressure of pure water at 55 °C is 0.1553 bar.The MW of lactose is

Accepted Answer

The answer of A solution is prepared by adding 30.00...

Question 9

At 20 °C,a 0.376 mol L^-1 aqueous solution of ammonium chloride has a density of What is the mass % of ammonium chloride in the solution? The formula weight of Cl is

Accepted Answer

The answer of At 20 °C,a 0.376 mol L^-1 aqueous...

Question 10

At a given temperature the vapour pressures of benzene and toluene are 183 mmHg and 59.2 mmHg,respectively.Calculate the total vapour pressure over a solution of benzene and toluene with x_benzene = 0.580.

Accepted Answer

The total vapour pressure over the solution can be calculated using Raoult's law: PTotal = X_benzene * PBenzene + (1 - X_benzene) * PToluene PTotal = 0.580 * 183 mmHg + (1 - 0.580) * 59.2 mmHg PTotal = 131 mmHg Therefore, the correct choice is C.

Question 11

Calculate the freezing point of a solution containing 5.0 grams of KCl and 550.0 grams of water.The molal freezing point depression constant (  )for water is

Accepted Answer

The answer of Calculate the freezing point of a solution...

Question 12

A solution is prepared by dissolving 40.0 g of sucrose,C₁₂H₂₂O₁₁,in 250.g of water at 25 °C.What is the vapour pressure of the solution if the vapour pressure of water at 25 °C is 23.76 mmHg?

Accepted Answer

The vapor pressure of the solution is calculated using Raoult's Law. The mole fraction of water is used to find the vapor pressure of the solution. The mole fraction of water is approximately 0.992, leading to a vapor pressure of about 23.6 mmHg.

Quiz 14: Solutions and Their Physical Properties

What is the expected freezing point of a 0.50 mol kg^-1 solution of Li₂SO₄ in water? K_f for water is 1.86 °C m^-1.

Which of the following solutions will have the lowest freezing point?

An aqueous solution has a normal boiling point of 103.0 °C.What is the freezing point of this solution? For water And

What is the freezing point of a solution of 7.15 g MgCl₂ in 100 g of water? K_f for water is

Calculate the freezing point of a solution of 40.0 g methyl salicylate,C₇H₆O₂,dissolved in 800.g of benzene,C₆H₆. And the freezing point is 5.50 °C for benzene.

A KCl solution is prepared by dissolving 25.0 g KCl in 250.0 g of water at 25 °C.What is the vapour pressure of the solution if the vapour pressure of water at 25 °C is 23.76 mmHg?

A solution is prepared by adding 30.00 g of lactose (milk sugar) to 110.0 g of water at The partial pressure of water above the solution is ________ Torr.The vapour pressure of pure water at 55 °C is 0.1553 bar.The MW of lactose is

At 20 °C,a 0.376 mol L^-1 aqueous solution of ammonium chloride has a density of What is the mass % of ammonium chloride in the solution? The formula weight of Cl is

At a given temperature the vapour pressures of benzene and toluene are 183 mmHg and 59.2 mmHg,respectively.Calculate the total vapour pressure over a solution of benzene and toluene with x_benzene = 0.580.

Calculate the freezing point of a solution containing 5.0 grams of KCl and 550.0 grams of water.The molal freezing point depression constant ( ) for water is

A solution is prepared by dissolving 40.0 g of sucrose,C₁₂H₂₂O₁₁,in 250.g of water at 25 °C.What is the vapour pressure of the solution if the vapour pressure of water at 25 °C is 23.76 mmHg?

Quiz 14: Solutions and Their Physical Properties

What is the expected freezing point of a 0.50 mol kg-1 solution of Li2SO4 in water? Kf for water is 1.86 °C m-1.

Which of the following solutions will have the lowest freezing point?

An aqueous solution has a normal boiling point of 103.0 °C.What is the freezing point of this solution? For water And

What is the freezing point of a solution of 7.15 g MgCl2 in 100 g of water? Kf for water is

Calculate the freezing point of a solution of 40.0 g methyl salicylate,C7H6O2,dissolved in 800.g of benzene,C6H6. And the freezing point is 5.50 °C for benzene.

A KCl solution is prepared by dissolving 25.0 g KCl in 250.0 g of water at 25 °C.What is the vapour pressure of the solution if the vapour pressure of water at 25 °C is 23.76 mmHg?

A solution is prepared by adding 30.00 g of lactose (milk sugar) to 110.0 g of water at The partial pressure of water above the solution is ________ Torr.The vapour pressure of pure water at 55 °C is 0.1553 bar.The MW of lactose is

At 20 °C,a 0.376 mol L-1 aqueous solution of ammonium chloride has a density of What is the mass % of ammonium chloride in the solution? The formula weight of Cl is

At a given temperature the vapour pressures of benzene and toluene are 183 mmHg and 59.2 mmHg,respectively.Calculate the total vapour pressure over a solution of benzene and toluene with xbenzene = 0.580.

Calculate the freezing point of a solution containing 5.0 grams of KCl and 550.0 grams of water.The molal freezing point depression constant ( ) for water is

A solution is prepared by dissolving 40.0 g of sucrose,C12H22O11,in 250.g of water at 25 °C.What is the vapour pressure of the solution if the vapour pressure of water at 25 °C is 23.76 mmHg?

What is the expected freezing point of a 0.50 mol kg^-1 solution of Li₂SO₄ in water? K_f for water is 1.86 °C m^-1.

What is the freezing point of a solution of 7.15 g MgCl₂ in 100 g of water? K_f for water is

Calculate the freezing point of a solution of 40.0 g methyl salicylate,C₇H₆O₂,dissolved in 800.g of benzene,C₆H₆. And the freezing point is 5.50 °C for benzene.

At 20 °C,a 0.376 mol L^-1 aqueous solution of ammonium chloride has a density of What is the mass % of ammonium chloride in the solution? The formula weight of Cl is

At a given temperature the vapour pressures of benzene and toluene are 183 mmHg and 59.2 mmHg,respectively.Calculate the total vapour pressure over a solution of benzene and toluene with x_benzene = 0.580.

A solution is prepared by dissolving 40.0 g of sucrose,C₁₂H₂₂O₁₁,in 250.g of water at 25 °C.What is the vapour pressure of the solution if the vapour pressure of water at 25 °C is 23.76 mmHg?