Question

What is the osmotic pressure (in atm) of a solution formed by dissolving 25.0 mg of CaCl2, in 250. mL of water at 25C?

Please show all work and explanations please!

Answer 1

molarity of CaCl2 solution (M) = 0.025 g/110.98 g/mol x 0.250 L = 9.01 x 10^-4 M

T = 25 oC + 273 = 198 K

R = gas constant

i = 3 (van;t hoff factor) for CaCl2

So,

osmotic pressure = iMRT

                             = 3 x 9.01 x 10^-4 x 0.08205 x 298

                             = 0.0661 atm