Question 1

A solution is made by mixing 50 grams of CHCl₃ (liquid) with 10 grams of CH₂Cl₂ (liquid). Which of the two is considered the solute and why?

Accepted Answer

CH₂Cl₂ is the solute because it is in the lesser amount compared to CHCl₃.

Question 2

How many milliliters of water must be added to 75.0 mL of 0.150 M AgNO₃ in order to prepare a 0.100 M solution? (Assume volumes are additive.)

Accepted Answer

To prepare the final concentration, we need to use the formula:
C1V1 = C2V2
where C1 and V1 are the concentration and volume of the initial solution, and C2 and V2 are the concentration and volume of the final solution. We know that C1 = 0.150 M, V1 = 75.0 mL, and C2 = 0.100 M. We can rearrange the formula to solve for V2:
V2 = (C1V1) / C2
V2 = (0.150 M x 75.0 mL) / 0.100 M
V2 = 112.5 mL
This is the total volume of the final solution. To find the amount of water needed, we can subtract the volume of the initial solution from the total volume of the final solution:
Water volume = V2 - V1
Water volume = 112.5 mL - 75.0 mL
Water volume = 37.5 mL
Therefore, we need to add 37.5 mL of water to the initial solution to prepare a 0.100 M solution. The closest answer choice is B, 38.0 mL of water.

Question 3

What mass of KCl is required to prepare 500 mL of a 2.50 M aqueous solution of KCl?
MM(KCl) = 74.55 g/mol.

Accepted Answer

To find the mass of KCl required, use the formula: mass = molarity × volume (L) × molar mass. Here, mass = 2.50 mol/L × 0.500 L × 74.55 g/mol = 93.2 g.

Question 4

Three hundred milliliters (300 mL) of 2.50 M sugar solution is diluted tO₆00 mL by the addition of pure water. Which of these statements about the solution is correct?

Accepted Answer

The moles of sugar remain constant because dilution involves adding solvent (water) without changing the amount of solute (sugar).

Question 5

Calculate the molarity of a solution prepared by dissolving 43.2 grams of pentane (C₅H₁₂, molar mass = 72.15 g/mol) in enough carbon tetrachloride (CCl₄, molar mass = 153.8 g/mol) to take 400 mL of solution.

Accepted Answer

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

Question 6

The molarity and molality of a solution:

Accepted Answer

Molarity and molality both express the quantity of solute in moles, but they differ in how they incorporate the solvent. Molarity is moles of solute per liter of solution, while molality is moles of solute per kilogram of solvent.

Question 7

What is the definition for mass percent solute ?

Accepted Answer

Mass percent solute refers to the mass of the solute (substance being dissolved) in a solution (mixture of solute and solvent) as a percentage of the total mass of the solution. Therefore, it is calculated by dividing the mass of the solute by the total mass of the solution (solute + solvent), and then multiplying by 100%. Option D represents this calculation. Option A is incorrect because it divides the mass of the solute by the mass of the solvent only. Options B and C are also incorrect because they do not take into account the total mass of the solution. Option E refers to the ratio of moles, which is irrelevant for calculating mass percent.

Question 8

How many grams of silver nitrate (AgNO₃) are present in 255 mL of 2.50 M silver nitrate solution? MM(AgNO₃) = 169.87 g/mol

Accepted Answer

The answer of How many grams of silver nitrate (AgNO₃)...

Question 9

A solution is made by mixing 25 grams of ethanol witH₅ grams of isopropanol. Which of the two is considered the solvent and why?

Accepted Answer

Ethanol is the solvent because it is present in the greater amount compared to isopropanol.

Question 10

How many grams of H₂SO₄ are present in 75.0 mL of 12.0 M H₂SO₄? MM (H₂SO₄) = 98.09 g/mol

Accepted Answer

First, we need to use the given concentration of the solution (12.0 M) to find the moles of H₂SO₄ present in 75.0 mL of the solution: molarity = moles / volume 12.0 M = moles / 0.075 L moles = 0.9 Next, we can use the molar mass of H₂SO₄ to convert moles to grams: grams = moles x molar mass grams = 0.9 x 98.09 grams = 88.3 Therefore, there are 88.3 grams of H₂SO₄ present in 75.0 mL of 12.0 M solution, making choice D the correct answer.

Question 11

How many grams of urea [CO(NH₂)₂] would be required to prepare 200 mL of a 5.0×10^{- 3} molar solution?

Accepted Answer

To find the mass of urea required, use the formula: mass = molarity × volume × molar mass. The molar mass of urea (CH4N2O) is approximately 60 g/mol. For a 5.0×10^-3 M solution in 200 mL (0.2 L), the mass is (5.0×10^-3 mol/L) × (0.2 L) × (60 g/mol) = 6.0×10^-2 g.

Question 12

Potassium fluoride is used for frosting glass. What is the molarity of a solution prepared by dissolving 78.6 g of KF in enough water to produce 225 mL of solution?
MM(KF) = 58.10 g/mol

Accepted Answer

The answer of Potassium fluoride is used for frosting glass....

Question 13

Which of the following concentration terms below represents moles of solute per kilogram of solvent?

Accepted Answer

Molality is defined as the number of moles of solute per kilogram of solvent, making it the appropriate concentration term for this question. Molarity (A) is the number of moles of solute per liter of solution, while molar mass (C) is the mass of one mole of a substance in grams. Mole fraction (D) is the ratio of the number of moles of one component in a mixture to the total number of moles in the mixture, and mole percent (E) is the mole fraction multiplied by 100.

Question 14

Calculate the molarity of glucose (C₆H₁₂O₆) in a solution in which 10.0 g of glucose is dissolved in water and diluted to a final volume of 200 mL.

Accepted Answer

The molar mass of glucose (C6H12O6) is approximately 180.16 g/mol. To find the molarity, divide the mass of glucose by its molar mass to get moles, then divide by the volume in liters. $ \frac{10.0 \, \text{g}}{180.16 \, \text{g/mol}} = 0.0555 \, \text{mol} $, and $ \frac{0.0555 \, \text{mol}}{0.2 \, \text{L}} = 0.2775 \, \text{M} $, which rounds to 0.278 M.

Question 15

How many grams of AgNO₃ are present in 50.0 mL of a 12.0 M AgNO₃ solution? MM(AgNO₃) = 169.88 g/mol

Accepted Answer

The answer of How many grams of AgNO₃ are present...

Question 16

What is the definition for molarity ?

Accepted Answer

Molarity is defined as the number of moles of solute dissolved in one liter of solution. Therefore, the correct option is E) Moles of solute per Liter of solution. Choice A refers to the concept of molality, B is incorrect as it has the unit of grams per solution, not mole per solution, and D refers to concentration in terms of mass, not moles.

Question 17

What is the definition for molality ?

Accepted Answer

Molality is defined as the number of moles of solute per kilogram of solvent in a solution. Option D represents this definition accurately. Option A is incorrect as it uses ‘mole of solvent’ instead of ‘kilogram of solvent’. Option B is the definition of Avogadro's number, not molality. Option C is the definition of molarity, which is the number of moles of solute per liter of solution. Option E does not specify if the moles of solute are in reference to the solvent or the solution.

Question 18

How many grams of solute are present in 164.1 mL of 0.207 M calcium acetate, Ca(C₂H₃O₂)₂? MM[Ca(C₂H₃O₂)₂] = 158.17 g/mol

Accepted Answer

The answer of How many grams of solute are present...

Question 19

How many grams of KBr are required to prepare 1.50 L of 0.257 M aqueous solution?
MM(KBr) = 119.00 g/mol

Accepted Answer

First, we need to use the formula:

Molarity (M) = moles of solute (n) / volume of solution in liters (V)

Rearranging the equation:

n = M x V

Substituting the given values:

n = 0.257 mol/L x 1.50 L = 0.3865 mol KBr

To convert moles to grams, we use the formula:

mass = moles x molar mass

Substituting the given values:

mass = 0.3865 mol x 119.00 g/mol = 45.9 g KBr

Therefore, the answer is C. 45.9 g KBr is required to prepare 1.50 L of 0.257 M aqueous solution.

Question 20

What volume in milliliters of a 0.200 M NaCl solution is required to provide 1.00 grams of NaCl?
MM(NaCl) = 58.44 g/mol

Accepted Answer

The answer of What volume in milliliters of a 0.200...

Quiz 12: Solutions

A solution is made by mixing 50 grams of CHCl₃ (liquid) with 10 grams of CH₂Cl₂ (liquid) . Which of the two is considered the solute and why?

How many milliliters of water must be added to 75.0 mL of 0.150 M AgNO₃ in order to prepare a 0.100 M solution? (Assume volumes are additive.)

What mass of KCl is required to prepare 500 mL of a 2.50 M aqueous solution of KCl? MM(KCl) = 74.55 g/mol.

Three hundred milliliters (300 mL) of 2.50 M sugar solution is diluted tO₆00 mL by the addition of pure water. Which of these statements about the solution is correct?

Calculate the molarity of a solution prepared by dissolving 43.2 grams of pentane (C₅H₁₂, molar mass = 72.15 g/mol) in enough carbon tetrachloride (CCl₄, molar mass = 153.8 g/mol) to take 400 mL of solution.

The molarity and molality of a solution:

What is the definition for mass percent solute ?

How many grams of silver nitrate (AgNO₃) are present in 255 mL of 2.50 M silver nitrate solution? MM(AgNO₃) = 169.87 g/mol

A solution is made by mixing 25 grams of ethanol witH₅ grams of isopropanol. Which of the two is considered the solvent and why?

How many grams of H₂SO₄ are present in 75.0 mL of 12.0 M H₂SO₄? MM (H₂SO₄) = 98.09 g/mol

How many grams of urea [CO(NH₂) ₂] would be required to prepare 200 mL of a 5.0×10^{- 3} molar solution?

Potassium fluoride is used for frosting glass. What is the molarity of a solution prepared by dissolving 78.6 g of KF in enough water to produce 225 mL of solution? MM(KF) = 58.10 g/mol

Which of the following concentration terms below represents moles of solute per kilogram of solvent?

Calculate the molarity of glucose (C₆H₁₂O₆) in a solution in which 10.0 g of glucose is dissolved in water and diluted to a final volume of 200 mL.

How many grams of AgNO₃ are present in 50.0 mL of a 12.0 M AgNO₃ solution? MM(AgNO₃) = 169.88 g/mol

What is the definition for molarity ?

What is the definition for molality ?

How many grams of solute are present in 164.1 mL of 0.207 M calcium acetate, Ca(C₂H₃O₂) ₂? MM[Ca(C₂H₃O₂) ₂] = 158.17 g/mol

How many grams of KBr are required to prepare 1.50 L of 0.257 M aqueous solution? MM(KBr) = 119.00 g/mol

What volume in milliliters of a 0.200 M NaCl solution is required to provide 1.00 grams of NaCl? MM(NaCl) = 58.44 g/mol

Quiz 12: Solutions

A solution is made by mixing 50 grams of CHCl3 (liquid) with 10 grams of CH2Cl2 (liquid) . Which of the two is considered the solute and why?

How many milliliters of water must be added to 75.0 mL of 0.150 M AgNO3 in order to prepare a 0.100 M solution? (Assume volumes are additive.)

What mass of KCl is required to prepare 500 mL of a 2.50 M aqueous solution of KCl? MM(KCl) = 74.55 g/mol.

Three hundred milliliters (300 mL) of 2.50 M sugar solution is diluted tO600 mL by the addition of pure water. Which of these statements about the solution is correct?

Calculate the molarity of a solution prepared by dissolving 43.2 grams of pentane (C5H12, molar mass = 72.15 g/mol) in enough carbon tetrachloride (CCl4, molar mass = 153.8 g/mol) to take 400 mL of solution.

The molarity and molality of a solution:

What is the definition for mass percent solute ?

How many grams of silver nitrate (AgNO3) are present in 255 mL of 2.50 M silver nitrate solution? MM(AgNO3) = 169.87 g/mol

A solution is made by mixing 25 grams of ethanol witH5 grams of isopropanol. Which of the two is considered the solvent and why?

How many grams of H2SO4 are present in 75.0 mL of 12.0 M H2SO4? MM (H2SO4) = 98.09 g/mol

How many grams of urea [CO(NH2) 2] would be required to prepare 200 mL of a 5.0×10 - 3 molar solution?

Potassium fluoride is used for frosting glass. What is the molarity of a solution prepared by dissolving 78.6 g of KF in enough water to produce 225 mL of solution? MM(KF) = 58.10 g/mol

Which of the following concentration terms below represents moles of solute per kilogram of solvent?

Calculate the molarity of glucose (C6H12O6) in a solution in which 10.0 g of glucose is dissolved in water and diluted to a final volume of 200 mL.

How many grams of AgNO3 are present in 50.0 mL of a 12.0 M AgNO3 solution? MM(AgNO3) = 169.88 g/mol

What is the definition for molarity ?

What is the definition for molality ?

How many grams of solute are present in 164.1 mL of 0.207 M calcium acetate, Ca(C2H3O2) 2? MM[Ca(C2H3O2) 2] = 158.17 g/mol

How many grams of KBr are required to prepare 1.50 L of 0.257 M aqueous solution? MM(KBr) = 119.00 g/mol

What volume in milliliters of a 0.200 M NaCl solution is required to provide 1.00 grams of NaCl? MM(NaCl) = 58.44 g/mol

A solution is made by mixing 50 grams of CHCl₃ (liquid) with 10 grams of CH₂Cl₂ (liquid) . Which of the two is considered the solute and why?

How many milliliters of water must be added to 75.0 mL of 0.150 M AgNO₃ in order to prepare a 0.100 M solution? (Assume volumes are additive.)

Three hundred milliliters (300 mL) of 2.50 M sugar solution is diluted tO₆00 mL by the addition of pure water. Which of these statements about the solution is correct?

Calculate the molarity of a solution prepared by dissolving 43.2 grams of pentane (C₅H₁₂, molar mass = 72.15 g/mol) in enough carbon tetrachloride (CCl₄, molar mass = 153.8 g/mol) to take 400 mL of solution.

How many grams of silver nitrate (AgNO₃) are present in 255 mL of 2.50 M silver nitrate solution? MM(AgNO₃) = 169.87 g/mol

A solution is made by mixing 25 grams of ethanol witH₅ grams of isopropanol. Which of the two is considered the solvent and why?

How many grams of H₂SO₄ are present in 75.0 mL of 12.0 M H₂SO₄? MM (H₂SO₄) = 98.09 g/mol

How many grams of urea [CO(NH₂) ₂] would be required to prepare 200 mL of a 5.0×10^{- 3} molar solution?

Calculate the molarity of glucose (C₆H₁₂O₆) in a solution in which 10.0 g of glucose is dissolved in water and diluted to a final volume of 200 mL.

How many grams of AgNO₃ are present in 50.0 mL of a 12.0 M AgNO₃ solution? MM(AgNO₃) = 169.88 g/mol

How many grams of solute are present in 164.1 mL of 0.207 M calcium acetate, Ca(C₂H₃O₂) ₂? MM[Ca(C₂H₃O₂) ₂] = 158.17 g/mol