1. What is the molarity of a solution which contains 0.256 mol of a substance dissolved in 143 mL of solution. 2. What is the molarity of a solution containing 4.89 g of NaCl dissolved in 600. mL of solution?

3. If 895 g of KCl is dissolved in 950. mL of solution, what is the molarity of the solution?

4. How many formula units of solute are there in a 5.50 L of 0.460 M silver nitrate solution.?

5. How many grams of FeCl2 are needed to make 700. mL of a 1.4 M solution?

6. Find the mass required to prepare 2500 mL of a 0.250 M solution of strontium sulfate.

7. Calculate the molarity of a solution when 75.0 g of calcium nitrite is dissolved in 500.0 mL of solution.

8. How many molecules of glucose (C6H12O6) are contained in 150.0 mL of a 0.100 M solution?

9. What mass of potassium bromide is needed to prepare 1.00 L of 0.250 M solution?

10. If I have 350 mL of a 0.400 M NaBr solution, what will the concentration be if I add 250. mL more water to it?

11. If I dilute 270. mL of 0.250 M lithium acetate solution to a volume of 800 mL, what will the concentration of this solution be?

12. The molar mass of an unknown gas is to be determined. The gas at STP occupies 0.861 L and its mass is 3.22 g. With this information calculate the molar mass of the gas. Theo claims the gas to be a noble gas. Assuming Theo to be correct, what would the identity of the gas be?

13. What mass of sulfur dioxide gas at STP is needed to fill a 300.0 mL volumetric flask?

14. Suppose you fill up a 5.00 L scuba tank with oxygen at STP. How many molecules of oxygen are there in the tank?

15. The store manager at Party City weighs the helium tank before opening the store and then at the end of the day. The mass of the helium before and after the working day are entered in the table below. How many atoms of helium gas at STP were used to fill up balloons in that day?

HINT: 1 lb = 454 g

Mass of helium tank before opening the store 1565 lb

Mass of helium tank after closing the store 1329 lb