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When 4.73 g of a nonelectrolyte solute is dissolved in water to make 585 mL of solution at 23 °C, the solution exerts an osmotic pressure of 959 torr. What is the molar concentration of the solution? How many moles of solute are in the solution? What is the molar mass of the solute?

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Final answer:

The molar concentration is 0.0517 M, there are 0.0302 moles of solute, and the molar mass of the solute is 156.6 g/mol for a solution made by dissolving 4.73 g of a nonelectrolyte in 585 mL of water at 23 °C with an osmotic pressure of 959 torr.

Step-by-step explanation:

To calculate the molar concentration of the solution when 4.73 g of nonelectrolyte solute is dissolved in 585 mL (0.585 L) of water, which exerts an osmotic pressure of 959 torr at 23 °C, we can use the formula II = MRT, where II is the osmotic pressure, M is the molarity, R is the ideal gas constant, and T is the temperature in kelvins.

First, convert the osmotic pressure from torr to atm: 959 torr = 959 torr * (1 atm / 760 torr) = 1.262 atm.

Assuming the ideal gas constant R is 0.0821 L·atm/(K·mol), and the temperature is 23 °C or 296 K (23 °C + 273 = 296 K), the molarity M can be found by rearranging the equation to M = II / (RT). Inserting the known values, we get:

M = 1.262 atm / [0.0821 L·atm/(K·mol) * 296 K]

M = 0.0517 mol/L.

To find the number of moles of solute in the solution, multiply the molarity by the volume of the solution in liters:

Moles of solute = 0.0517 mol/L * 0.585 L = 0.0302 mol.

The molar mass of the solute can be calculated by dividing the mass of the solute by the number of moles:

Molar mass = 4.73 g / 0.0302 mol = 156.6 g/mol.

In summary, the molar concentration is 0.0517 M, there are 0.0302 moles of solute in the solution, and the molar mass of the solute is 156.6 g/mol.

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