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A solution containing 2.75 g of a nonelectrolyte polymer dissolved in 150.0 solution has osmotic pressure of 1.25 * 10 ^ - 2 atm at 130 deg * C Calculate the molar mass of the polymer Make sure to use complete units.

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Answer:

11824 g/mol

Step-by-step explanation:

To calculate the molar mass of the polymer, we need to use the equation for osmotic pressure:

π = MRT

where π is the osmotic pressure, M is the molarity of the solution, R is the gas constant, and T is the temperature in Kelvin.

We can rearrange this equation to solve for the molarity of the solution:

M = π / RT

We can then use the molarity to calculate the number of moles of the polymer:

moles of polymer = molarity * volume

where volume is the volume of the solution in liters.

Finally, we can use the number of moles and the mass of the polymer to calculate the molar mass:

molar mass = mass of polymer / moles of polymer

Let's plug in the given values and solve for the molar mass:

π = 1.25 × 10^-2 atm

mass of polymer = 2.75 g

volume = 150.0 mL = 0.1500 L

R = 0.08206 L atm mol^-1 K^-1

T = 130 + 273.15 = 403.15 K

First, let's calculate the molarity:

M = π / RT = (1.25 × 10^-2 atm) / (0.08206 L atm mol^-1 K^-1 × 403.15 K) = 0.00155 M

Next, let's calculate the number of moles of the polymer:

moles of polymer = molarity × volume = (0.00155 mol/L) × 0.1500 L = 0.0002325 mol

Finally, let's calculate the molar mass:

molar mass = mass of polymer / moles of polymer = 2.75 g / 0.0002325 mol = 11824 g/mol

Therefore, the molar mass of the polymer is 11824 g/mol.


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