Question 1

A person is considered legally intoxicated with a blood alcohol level of 80 mg/dL.Assuming that blood plasma has a density of 1.025 g/mL,what is this concentration expressed in parts per million?

Accepted Answer

The answer of A person is considered legally intoxicated with...

Question 2

Calculate the freezing point of a solution of 30.0 g methyl salicylate,C₇H₆O₂,dissolved in 800.g of benzene,C₆H₆.K_f for benzene is 5.10°C/m and the freezing point is 5.50°C for benzene.

Accepted Answer

First, calculate the molality of the solution: Molar mass of C7H6O2 = 138.12 g/mol. Moles of solute = 30.0 g / 138.12 g/mol = 0.217 mol. Molality (m) = 0.217 mol / 0.800 kg = 0.27125 m. Freezing point depression (ΔTf) = Kf * m = 5.10°C/m * 0.27125 m = 1.38°C. New freezing point = 5.50°C - 1.38°C = 4.12°C. The closest option is 3.93°C.

Question 3

A 0.50 m solution of which solute has the largest van't Hoff factor?

Accepted Answer

Li₃PO₄ dissociates into 4 ions (3 Li⁺ and 1 PO₄^3-), giving it the largest van't Hoff factor among the options.

Question 4

In a solution that is 75% ethyl alcohol and 25% water,the solute is ________ and the solvent is ________.

Accepted Answer

The answer of In a solution that is 75% ethyl...

Question 5

The volume of 0.200 M H₂SO₄ that contains 5.00 mmol of H⁺ is ________ mL.

Accepted Answer

The answer of The volume of 0.200 M H₂SO₄ that...

Question 6

A 0.020 m aqueous solution containing which solute will have the lowest freezing point?

Accepted Answer

The freezing point depression is directly proportional to the molality of the solution. All the given solutes are 1:1 electrolytes, so they will all produce the same number of ions in solution and have the same molality. Therefore, they will all have approximately the same freezing point.

Question 7

When 2.36 g of a nonvolatile solute is dissolved in 100 g of solvent,the largest change in freezing point will be achieved when the solvent is

Accepted Answer

The largest change in freezing point is achieved with the solvent that has the highest molal freezing point depression constant (Kf). In this case, tert-butanol has the highest Kf value of 9.1, indicating it will produce the largest change in freezing point when a nonvolatile solute is dissolved in it.

Question 8

Amphetamines in urine can be confirmed by mass spectroscopy at a concentration of 500 ng/mL.Assuming a urine density of 1.025 g/mL,what is this concentration in parts per million?

Accepted Answer

The answer of Amphetamines in urine can be confirmed by...

Question 9

What is the freezing point of a solution of 2.86 g MgCl₂ in 100 g of water? K_f for water is 1.86°C/m.

Accepted Answer

The freezing point depression is calculated using ΔTf = i * Kf * m, where i is the van't Hoff factor (3 for MgCl2), Kf is 1.86°C/m, and m is the molality. Molality is calculated as moles of solute per kg of solvent. Moles of MgCl2 = 2.86 g / 95.21 g/mol = 0.03 mol. Molality = 0.03 mol / 0.1 kg = 0.3 m. ΔTf = 3 * 1.86°C/m * 0.3 m = 1.674°C. The freezing point is 0°C - 1.674°C = -1.67°C.

Question 10

The number of moles of ions in 35.0mL of 4.00 M Na₂SO₄ is ________ moles.

Accepted Answer

The answer of The number of moles of ions in...

Question 11

Which of the following pairs of solutions have roughly the same boiling point elevation?

Accepted Answer

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Question 12

An aqueous solution has a normal boiling point of 102.5°C.What is the freezing point of this solution? For water K_b = 0.51°C/m and K_f = 1.86°C/m.

Accepted Answer

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

Question 13

According to the rule of thumb "like dissolves like" ionic solids like LiF or polar substances like glucose are more soluble in ________ solvents,whereas nonpolar substances like I₂ are more soluble in ________ solvents.

Accepted Answer

The answer of According to the rule of thumb "like...

Question 14

Chloroform has a boiling point of 61.1°C and dichloromethane has a boiling point of 40.0°C.When 0.250 mol of dichloromethane is added to 0.750 mol of chloroform,the resulting solution will have a boiling point

Accepted Answer

Since the boiling point of a solution is dependent on the number of solute particles in the solution, adding dichloromethane (0.250 mol) to chloroform (0.750 mol) will increase the number of solute particles present in the solution. This will result in an increase in the boiling point of the solution. However, since dichloromethane has a lower boiling point than chloroform, the resulting solution will have a boiling point closer to that of chloroform (61.1°C) but still higher than dichloromethane (40.0°C), so the answer is between 40.0°C and 61.1°C, but closer to 61.1°C, which is option A.

Question 15

Cocaine,C₁₇H₂₁NO₄,in urine can be confirmed by mass spectroscopy at a concentration of 150 ng/mL.Assuming a urine density of 1.025 g/mL,what is this concentration expressed as molality?

Accepted Answer

The answer of Cocaine,C₁₇H₂₁NO₄,in urine can be confirmed by mass...

Question 16

Molarity is defined as ________,whereas molality is defined as ________.

Accepted Answer

The answer of Molarity is defined as ________,whereas molality is...

Question 17

When KI is dissolved in water,the major forces overcome are ________ forces in the solute and ________ forces in the solvent,and the major forces created between solute and solvent particles are ________ forces.

Accepted Answer

The answer of When KI is dissolved in water,the major...

Question 18

A 0.35 m aqueous solution of an unknown solute has a boiling point elevation of 0.79°C.The boiling point elevation of a 0.35 m solution of a nonionizing molecular solute in water is 0.33°C.How many moles of particles are formed per mole of solute when the unknown solute is dissolved in water?

Accepted Answer

The boiling point elevation is proportional to the number of particles in solution. The unknown solute causes a greater elevation (0.79°C) than the nonionizing solute (0.33°C), indicating it dissociates into more particles. The ratio of 0.79/0.33 is approximately 2.4, suggesting 2.4 moles of particles are formed per mole of solute.

Question 19

A solution is made by dissolving 19.5 g of sucrose,C₁₂H₂₂O₁₁,in 117 g of water,producing a solution with a volume of 125 mL at 20°C.What is the expected osmotic pressure at 20°C?

Accepted Answer

The osmotic pressure ($\Pi$) can be calculated using the formula $\Pi = iMRT$, where $i$ is the van't Hoff factor (which is 1 for sucrose since it doesn't ionize in solution), $M$ is the molarity of the solution, $R$ is the ideal gas constant (0.0821 L·atm/K·mol), and $T$ is the temperature in Kelvin. First, convert the mass of sucrose to moles ($\frac{19.5 g}{342.3 g/mol}$), then calculate the molarity ($\frac{moles}{0.125 L}$), and finally, use the formula with $T = 293 K$ (20°C + 273). The calculation yields approximately 11.0 atm.

Question 20

Calculate the freezing point of a solution when 370 grams of Ca₃(PO₄)is added to 3000mL of water.(density of water is 1.00 g/mL).The K_f for water is 1.86°C/m and normal freezing point of water is 0.00°C.

Accepted Answer

First, we need to calculate the molality of the solution: molality = moles of solute / mass of solvent in kg The molar mass of Ca₃(PO₄) is 40.078 g/mol + 32.066 g/mol + 13(15.999 g/mol) + 1(30.974 g/mol) = 407.642 g/mol moles of Ca₃(PO₄) = 370 g / 407.642 g/mol = 0.907 mol mass of solvent (water) = 3000 mL x 1.00 g/mL = 3000 g = 3 kg molality = 0.907 mol / 3 kg = 0.302 mol/kg Using the freezing point depression equation: ΔTf = Kf x molality where ΔTf = change in freezing point and Kf = freezing point depression constant. We can calculate the freezing point depression: ΔTf = 1.86°C/m x 0.302 mol/kg = 0.56172°C Finally, we can calculate the freezing point of the solution: freezing point = normal freezing point - ΔTf = 0.00°C - 0.56172°C = -0.56172°C Therefore, the answer is C) -3.70 (rounded to two decimal places).

Quiz 12: Solutions and Their Properties

A person is considered legally intoxicated with a blood alcohol level of 80 mg/dL.Assuming that blood plasma has a density of 1.025 g/mL,what is this concentration expressed in parts per million?

Calculate the freezing point of a solution of 30.0 g methyl salicylate,C₇H₆O₂,dissolved in 800.g of benzene,C₆H₆.K_f for benzene is 5.10°C/m and the freezing point is 5.50°C for benzene.

A 0.50 m solution of which solute has the largest van't Hoff factor?

In a solution that is 75% ethyl alcohol and 25% water,the solute is and the solvent is .

The volume of 0.200 M H₂SO₄ that contains 5.00 mmol of H⁺ is ________ mL.

A 0.020 m aqueous solution containing which solute will have the lowest freezing point?

When 2.36 g of a nonvolatile solute is dissolved in 100 g of solvent,the largest change in freezing point will be achieved when the solvent is

Amphetamines in urine can be confirmed by mass spectroscopy at a concentration of 500 ng/mL.Assuming a urine density of 1.025 g/mL,what is this concentration in parts per million?

What is the freezing point of a solution of 2.86 g MgCl₂ in 100 g of water? K_f for water is 1.86°C/m.

The number of moles of ions in 35.0mL of 4.00 M Na₂SO₄ is ________ moles.

Which of the following pairs of solutions have roughly the same boiling point elevation?

An aqueous solution has a normal boiling point of 102.5°C.What is the freezing point of this solution? For water K_b = 0.51°C/m and K_f = 1.86°C/m.

According to the rule of thumb "like dissolves like" ionic solids like LiF or polar substances like glucose are more soluble in solvents,whereas nonpolar substances like I₂ are more soluble in solvents.

Chloroform has a boiling point of 61.1°C and dichloromethane has a boiling point of 40.0°C.When 0.250 mol of dichloromethane is added to 0.750 mol of chloroform,the resulting solution will have a boiling point

Cocaine,C₁₇H₂₁NO₄,in urine can be confirmed by mass spectroscopy at a concentration of 150 ng/mL.Assuming a urine density of 1.025 g/mL,what is this concentration expressed as molality?

Molarity is defined as ,whereas molality is defined as .

When KI is dissolved in water,the major forces overcome are forces in the solute and forces in the solvent,and the major forces created between solute and solvent particles are forces.

A 0.35 m aqueous solution of an unknown solute has a boiling point elevation of 0.79°C.The boiling point elevation of a 0.35 m solution of a nonionizing molecular solute in water is 0.33°C.How many moles of particles are formed per mole of solute when the unknown solute is dissolved in water?

A solution is made by dissolving 19.5 g of sucrose,C₁₂H₂₂O₁₁,in 117 g of water,producing a solution with a volume of 125 mL at 20°C.What is the expected osmotic pressure at 20°C?

Calculate the freezing point of a solution when 370 grams of Ca₃(PO₄) is added to 3000mL of water.(density of water is 1.00 g/mL) .The K_f for water is 1.86°C/m and normal freezing point of water is 0.00°C.

Quiz 12: Solutions and Their Properties

A person is considered legally intoxicated with a blood alcohol level of 80 mg/dL.Assuming that blood plasma has a density of 1.025 g/mL,what is this concentration expressed in parts per million?

Calculate the freezing point of a solution of 30.0 g methyl salicylate,C7H6O2,dissolved in 800.g of benzene,C6H6.Kf for benzene is 5.10°C/m and the freezing point is 5.50°C for benzene.

A 0.50 m solution of which solute has the largest van't Hoff factor?

In a solution that is 75% ethyl alcohol and 25% water,the solute is ________ and the solvent is ________.

The volume of 0.200 M H2SO4 that contains 5.00 mmol of H+ is ________ mL.

A 0.020 m aqueous solution containing which solute will have the lowest freezing point?

When 2.36 g of a nonvolatile solute is dissolved in 100 g of solvent,the largest change in freezing point will be achieved when the solvent is

Amphetamines in urine can be confirmed by mass spectroscopy at a concentration of 500 ng/mL.Assuming a urine density of 1.025 g/mL,what is this concentration in parts per million?

What is the freezing point of a solution of 2.86 g MgCl2 in 100 g of water? Kf for water is 1.86°C/m.

The number of moles of ions in 35.0mL of 4.00 M Na2SO4 is ________ moles.

Which of the following pairs of solutions have roughly the same boiling point elevation?

An aqueous solution has a normal boiling point of 102.5°C.What is the freezing point of this solution? For water Kb = 0.51°C/m and Kf = 1.86°C/m.

According to the rule of thumb "like dissolves like" ionic solids like LiF or polar substances like glucose are more soluble in ________ solvents,whereas nonpolar substances like I2 are more soluble in ________ solvents.

Chloroform has a boiling point of 61.1°C and dichloromethane has a boiling point of 40.0°C.When 0.250 mol of dichloromethane is added to 0.750 mol of chloroform,the resulting solution will have a boiling point

Cocaine,C17H21NO4,in urine can be confirmed by mass spectroscopy at a concentration of 150 ng/mL.Assuming a urine density of 1.025 g/mL,what is this concentration expressed as molality?

Molarity is defined as ________,whereas molality is defined as ________.

When KI is dissolved in water,the major forces overcome are ________ forces in the solute and ________ forces in the solvent,and the major forces created between solute and solvent particles are ________ forces.

A 0.35 m aqueous solution of an unknown solute has a boiling point elevation of 0.79°C.The boiling point elevation of a 0.35 m solution of a nonionizing molecular solute in water is 0.33°C.How many moles of particles are formed per mole of solute when the unknown solute is dissolved in water?

A solution is made by dissolving 19.5 g of sucrose,C12H22O11,in 117 g of water,producing a solution with a volume of 125 mL at 20°C.What is the expected osmotic pressure at 20°C?

Calculate the freezing point of a solution when 370 grams of Ca3(PO4) is added to 3000mL of water.(density of water is 1.00 g/mL) .The Kf for water is 1.86°C/m and normal freezing point of water is 0.00°C.

Calculate the freezing point of a solution of 30.0 g methyl salicylate,C₇H₆O₂,dissolved in 800.g of benzene,C₆H₆.K_f for benzene is 5.10°C/m and the freezing point is 5.50°C for benzene.

In a solution that is 75% ethyl alcohol and 25% water,the solute is and the solvent is .

The volume of 0.200 M H₂SO₄ that contains 5.00 mmol of H⁺ is ________ mL.

What is the freezing point of a solution of 2.86 g MgCl₂ in 100 g of water? K_f for water is 1.86°C/m.

The number of moles of ions in 35.0mL of 4.00 M Na₂SO₄ is ________ moles.

An aqueous solution has a normal boiling point of 102.5°C.What is the freezing point of this solution? For water K_b = 0.51°C/m and K_f = 1.86°C/m.

According to the rule of thumb "like dissolves like" ionic solids like LiF or polar substances like glucose are more soluble in solvents,whereas nonpolar substances like I₂ are more soluble in solvents.

Cocaine,C₁₇H₂₁NO₄,in urine can be confirmed by mass spectroscopy at a concentration of 150 ng/mL.Assuming a urine density of 1.025 g/mL,what is this concentration expressed as molality?

Molarity is defined as ,whereas molality is defined as .

When KI is dissolved in water,the major forces overcome are forces in the solute and forces in the solvent,and the major forces created between solute and solvent particles are forces.

A solution is made by dissolving 19.5 g of sucrose,C₁₂H₂₂O₁₁,in 117 g of water,producing a solution with a volume of 125 mL at 20°C.What is the expected osmotic pressure at 20°C?

Calculate the freezing point of a solution when 370 grams of Ca₃(PO₄) is added to 3000mL of water.(density of water is 1.00 g/mL) .The K_f for water is 1.86°C/m and normal freezing point of water is 0.00°C.