Unit 6 Solutions Review

Which of the following best describes what happens when an ionic compound dissolves in water?

• The ionic compound breaks into smaller molecules but remains solid.

• The ionic compound dissociates into positive and negative ions.

• The ionic compound reacts chemically to form a new substance.

• The ionic compound forms a suspension instead of a solution.

Which of the following factors does NOT affect how fast a solute dissolves in a solvent?

• Temperature of the solvent

• Stirring the solution

• Color of the solute

• Size of the solute particles

A student adds sugar to cold water and notices that only a small amount dissolves. What is the best way to increase the solubility of the sugar?

• Decrease the temperature of the water

• Stir the solution while keeping it cold

• Increase the temperature of the water

• Use larger sugar crystals

Which of the following correctly represents the dissociation equation for Al₂(SO₄)₃ in water?

• Al₂(SO₄)₃ (s) → 2 Al³⁺ (aq) + 3 SO₄²⁻ (aq)

• Al₂(SO₄)₃ (s) → Al₂(SO₄)₃ (aq)

• Al₂(SO₄)₃ (s) → Al³⁺ (aq) + SO₄²⁻ (aq)

• Al₂(SO₄)₃ (s) → 2 Al³⁺ (s) + 3 SO₄²⁻ (s)

Tags

NGSS.HS-PS1-7

When dissolving CaCl₂ in water, which of the following is the correct dissociation equation?

• CaCl₂ (s) → Ca²⁺ (aq) + Cl⁻ (aq)

• CaCl₂ (s) → CaCl₂ (aq)

• CaCl₂ (s) → Ca²⁺ (aq) + 2 Cl⁻ (aq)

• CaCl₂ (s) → Ca (s) + 2 Cl⁻ (s)

Tags

NGSS.HS-PS1-7

A scientist takes 10.0 mL of a 3.0 M NaCl solution and transfers 5.0 mL into a new test tube, then dilutes it with distilled water until the final volume is 10.0 mL. What is the new concentration of NaCl in the second test tube?

• A) 3.0 M

• B) 1.5 M

• C) 6.0 M

• D) 0.75 M

A student needs to prepare 250.0 mL of a 0.50 M NaCl solution. If the stock solution is 2.0 M, what volume of the stock solution should they use?

• A) 62.5 mL

• B) 125.0 mL

• C) 250.0 mL

• D) 500.0 mL

Tags

NGSS.HS-PS1-7

A chemist wants to dilute 100.0 mL of a 4.0 M solution to a final concentration of 1.0 M. What should the final volume of the solution be after dilution?

• A) 25.0 mL

• B) 100.0 mL

• C) 200.0 mL

• D) 400.0 mL

What is the molarity of a solution prepared by dissolving 5.0 moles of NaCl in 2.0 L of water?

• A) 0.40 M

• B) 2.5 M

• C) 5.0 M

• D) 10.0 M

A student prepares a 0.10 M solution by performing a serial dilution from a 1.0 M solution. What is the dilution factor at each step if the student performs two equal dilutions?

• A) 2

• B) 5

• C) 10

• D) 100