Determine the mass of sodium chloride, NaCl, that must be added to water to create an aqueous solution of volume 0.50 dm³ with an osmotic pressure of 1.0 atm at 298 K.

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The correct answer is A.The osmotic pressure of a solution is given by the van't Hoff equation:$$\pi = MRT$$where:* $\pi$ is the osmotic pressure in atm* $M$ is the molarity of the solution in mol/dm³* $R$ is the ideal gas constant in dm³ atm/(mol K)* $T$ is the temperature in KWe are given that the osmotic pressure is 1.0 atm, the volume of the solution is 0.50 dm³, and the temperature is 298 K. We can use the van't Hoff equation to calculate the molarity of the solution:$$1.0 \text{ atm} = M \times 0.0821 \text{ dm}^3 \text{ atm}/(\text{mol K}) \times 298 \text{ K}$$$$M = 0.0417 \text{ mol/dm}^3$$We can then use the molarity of the solution to calculate the mass of NaCl that must be added to the water:$$0.0417 \text{ mol/dm}^3 \times 0.50 \text{ dm}^3 \times 58.44 \text{ g/mol} = 1.19 \text{ g}$$Therefore, the mass of NaCl that must be added to the water is 1.19 g.

Determine the Mass of Sodium Chloride, NaCl, That Must Be