Practice Problems – molality (m)

1) Calculate the molality when 75.0 grams of MgCl2 is dissolved in 500.0 g of solvent.

2) 100.0 grams of sucrose (C12H22O11, mol. wt. = 342.3 g/mol) is dissolved in 1.50 L of water. What is the molality?

3) 49.8 grams of KI is dissolved in 1.00 kg of solvent. What is the molality?

4)  Determine the molal concentration of a solution in which 320 grams of glucose C6H12O6 are dissolved in 4000 grams of water. 

5)	How many grams MgCl2 will be needed to prepare 3000 grams of a 0.8 molal solution?
*** #5 is a challenge problem.  HINT:  Define and use “x” carefully!