Understanding Solution Concentrations

What is the formula for calculating molarity?

• M = moles of solute / liters of solution

• M = moles of solution / liters of solute

• M = grams of solute / liters of solution

• M = moles of solute / grams of solution

How do you calculate molality from moles of solute and mass of solvent?

• molality (m) = mass of solvent / moles of solute

• molality (m) = moles of solute + mass of solvent (kg)

• molality (m) = moles of solute * mass of solvent (kg)

• molality (m) = moles of solute / mass of solvent (kg)

If you dilute a 2 M solution to 1 M, what is the dilution factor?

• 3

• 1.5

• 0.5

• 2

What is the difference between molarity and molality?

• Molarity is a measure of temperature, while molality is a measure of pressure.

• Molarity is based on the number of moles, while molality is based on the number of molecules.

• Molarity measures concentration in terms of volume, while molality measures concentration in terms of mass.

• Molarity is used for gases, while molality is used for liquids.

How do you prepare a 0.5 M NaCl solution from solid NaCl?

• Dissolve 58.44 g of NaCl in 500 mL of water.

• Dissolve 29.22 g of NaCl in 2 L of water.

• Dissolve 29.22 g of NaCl in enough water to make 1 L of solution.

• Dissolve 14.61 g of NaCl in enough water to make 1 L of solution.

What is the unit of molarity?

• mol/kg

• mol/cc

• mol/mL

• mol/L

How do you convert molarity to molality?

• m = (M * density of solution) / (1 - (M * molar mass of solute))

• m = M * molar mass of solute

• m = M / density of solution

• m = (M * volume of solution) / molar mass of solute

If you have 100 mL of a 3 M solution, how many moles of solute do you have?

• 0.5 moles

• 0.3 moles

• 0.1 moles

• 1 mole

What is the formula for percent by mass concentration?

• Percent by mass = (mass of solute / mass of solvent) x 100

• Percent by mass = (mass of solute / total mass of solution) x 100

• Percent by mass = (mass of solution / mass of solute) x 100

• Percent by mass = (volume of solute / total volume of solution) x 100

How do you calculate the final concentration after dilution?

• C2 = V2 - C1

• C2 = V1 / C1

• C2 = C1 + V1

• C2 = (C1V1) / V2