DE Unit 4_Concentration & Colligative Properties_F2021

What is the mole fraction of MgF₂ in a solution  that has 0.321 mol of MgF₂ dissolved in 4.44 mol of water?

• 0.0674
• 0.0722
• 1.425

What is the molarity of 122.5 g of AlCl₃ in 1.0 L of solution?

• 1.225 M
• 0.92 M
• 0.1225 M

What is the mole fraction of ethanol when 0.504 mol of ethanol are mixed with 4.06 mol of water?

• 0.110
• 0.124
• 0.097

How many moles of barium chloride are in 427 g of a 3.17% by mass barium chloride solution?

• 13.5 mol

• 0.065 mol

• 0.0431 mol

• 4.27 mol

The mole fraction of copper (II) nitrate in an aqueous solution is 0.135. What is the molality of the solution?

• 8.67

• 8.01

• 7.49

• 9.34

An aqueous solution of citric acid (H₃C₆H₅O₇) has a molality of 0.688. If the density of the solution is 1.049 g/mL, what is the molarity?

• 0.638 M

• 0.586 M

• 2.512 M

• 0.722 M

If 291 g of a solute (non-dissociating) is added to 1.02 kg of water increases the boiling point by 5.77°C, what is the molar mass of the compound?

• 25.3 g/mol

• 28.5 g/mol

• 30.3 g/mol

• 18.3 g/mol

A 5.1 g sample of CaCl₂ is dissolved in a beaker of water. Which of the following statements is true for the solution?

• The solution will freeze at a lower temperature than the pure solvent

• The solution has a higher vapor pressure than the pure solvent

• The solution will boil at a lower temperature than the pure solvent

• All of the above are true

When KCl (potassium chloride) is dissolved in water, how many particles are in solution for each unit?

• 1

• 2

• 3

• 4

• 6

What is the freezing point of a 1.5 m solution of sucrose in water? (K_f = 1.86°C/m)

• -2.8°C
• -1.2°C
• -0.81°C
• 0.81°C