Concentration and Dilution

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

What volume is needed to make a 2.45 M solution of KCl using 0.50 mol of KCl?

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

What is the percent by mass of a solution made by dissolving 20.0 g of NaCl into 180.0 g of water?

Answer explanation

20g / (180g+ 20g) x 100 = 10 %

What is the concentration, in percent by volume, of 15.3 mL of solute in 2.65 L of solution?

What is the mole fraction of NaOH in an aqueous solution that contains 22.8% NaOH by mass?

(1L of H₂O has a mass of 1000g, 1 mol H₂O = 18.02g)

What is the concentration of a solution in parts per million if 0.02 grams of NaCl is dissolved in 1000 grams of solution?

Concentration is

• the amount of solute in the solvent

• the amount of solvent in the solute

• density

• particle size

Tags

NGSS.HS-PS1-5

Which solution is more concentrated?

Solution 1:

500 mL of water

100 g of salt

Solution 2:

500 mL of water

90 g of salt

• Solution 1

• Solution 2

• They have the same concentration

• I have no idea

Tags

NGSS.HS-PS1-5

In order to dilute a solution, you need to

• add more of the solid

• add more water

• find the mass

• find the volume