Practice -Solution Concentrations
1. When a NaCl solution was prepared in lab, 250.0 g of NaCl was dissolved in 4.0 L of water.
a. Is NaCl the solute or the solvent?
b. Is water the solute or the solvent.
c. Is NaCl an ionic or covalent compound?
d. Is this solution an electrolyte or a nonelectrolyte?
e. Determine the molarity of this NaCl solution. (1.08 M)
f. What is the concentration in g/L? (62.5 g/L)
2. How much HCl will be needed to produce a 40 L of a 2 M solution? (Hint: First, determine the
moles produced and then convert this number of moles to mass in grams) (2960 g)
3. What is the molality of KCl solution when 85.0 g of KCl is dissolved in 100 ml of water?
(Hint: 1 g of water = 1 ml of water) (.12 m)
4. An sample of water was found to have 0.5 mg of an unknown toxin in a 400 ml sample of water.
Determine the concentration of this unknown toxin in ppm. (1.25 ppm)
5. If a 650 ml sample of water contains .24 mg of a pollutant, determine the concentration in ppm
of this pollutant. (.37 ppm)
6. Calculate the % composition of:
a. Hg2Cl2 ( Hg= 85%, Cl=15%)
b. Ba3(PO4)2 (Ba= 69%, P= 10%, O= 21%)
7. Determine the percent of water in Ba(OH)2 8H2O (45.71%)
Practice-Solution Concentrations
1. When a NaCl solution was prepared in lab, 250.0 g of NaCl was dissolved in 4.0 L of water.
a. Is NaCl the solute or the solvent?
b. Is water the solute or the solvent.
c. Is NaCl an ionic or covalent compound?
d. Is this solution an electrolyte or a nonelectrolyte?
e. Determine the molarity of this NaCl solution. (1.08 M)
f. What is the concentration in g/L? (62.5 g/L)
2. How much HCl will be needed to produce a 40 L of a 2 M solution? (Hint: First, determine the
moles produced and then convert this number of moles to mass in grams) (2960 g)
3. What is the molality of KCl solution when 85.0 g of KCl is dissolved in 100 ml of water?
(Hint: 1 g of water = 1 ml of water) (.12 m)
4. An sample of water was found to have 0.5 mg of an unknown toxin in a 400 ml sample of water.
Determine the concentration of this unknown toxin in ppm. (1.25 ppm)
5. If a 650 ml sample of water contains .24 mg of a pollutant, determine the concentration in ppm
of this pollutant. (.37 ppm)
6. Calculate the % composition of:
a. Hg2Cl2 ( Hg= 85%, Cl=15%)
b. Ba3(PO4)2 (Ba= 69%, P= 10%, O= 21%)
7. Determine the percent of water in Ba(OH)2 8H2O (45.71%)