Concentration Units in Solutions

Which of the following is the correct unit for molarity?

• mol/kg

• mol/g

• M/L

• mol/L

Which concentration unit is affected by changes in temperature?

• Neither molarity nor molality

• Molality

• Both molarity and molality

• Molarity

What is the molality of a solution made by dissolving 2 moles of NaOH in 400 grams of water?

• 5 mol/L

• 3 mol/kg

• 2.5 mol/L

• 5 mol/kg

A solution that is considered unsaturated would _____.

• have a small amount of solute.

• have a strong scent.

• have a large amount of solute.

• be dark in color.

Molality is preferred over molarity when working with solutions at different temperatures because volume changes with temperature.

• true

• False

If 0.5 moles of solute are dissolved in 250 grams of solvent, what is the molality of the solution?

• 0.2m

• 0.5m

• 2 m

• 5 m

What is the molarity of a solution made by dissolving 58.5 grams of NaCl (molar mass = 58.5 g/mol) in enough water to make 1 liter of solution?

• 0.5 M

• 1 M

• 2 M

• 58.5 M

In a diluted solution, the molarity decreases while the number of moles of solute remains the same.

• True

• False

When the temperature increases, the molarity of a solution may decrease because the ____ of the solution increases.

• Mass

• Density

• Volume

• Molality

What is the molarity of a 0.5L sample of a solution that contains 60.0 g of sodium hydroxide (NaOH)?

• 0.8 M

• 3.0 M

• 6.0 M

• 5.0 M