Now recall that osmotic pressure is the force that drives the movement of water from a lower concentration to a higher concentration. And remember that the osmotic pressure of a solution can be influenced by its concentration and temperature. So if we take a look here, we have our osmotic pressure formula. Here we're going to say that osmotic pressure, which is represented by this pi symbol, is in units of atmospheres, and it equals I, which is your van't Hoff factor, capital M, which is your molarity or concentration or solubility. Okay. And that will be in moles per liter, so moles of solute over liters of solution, times R. R is your gas constant, which is 0.08206, liters times atmospheres over moles times K. And then here, finally, T is our temperature and that would be in units of Kelvin. So just remember, when it comes to osmotic pressure, concentration and temperature can play a role in influencing the osmotic pressure of any solution.
π = I M R = 0.08206 TOsmotic Pressure - Online Tutor, Practice Problems & Exam Prep
Osmotic Pressure is the force that drives Osmosis from higher concentration to lower concentration.
Osmotic Pressure Calculations
Osmotic Pressure Concept 1
Video transcript
Osmotic Pressure Example 1
Video transcript
Here it says calculate the osmotic pressure of the solution that is 18.30 milligrams of zinc oxide and 15.1 ml of solution at 26 degrees Celsius. Alright. So osmotic pressure equals I⋅M⋅R⋅T. Zinc oxide is an ionic solute that breaks up into zinc ion and oxide ion. That's 2 ions, so I=2. M (capital) is our molarity which is moles over liters. Here, when I convert the 15 ml into liters, that's 0.015 liters. Then I can change the 18.30 milligrams of Zinc into moles. So remember 1 milligram is 10-3 grams and 1 mole of zinc, the weight of zinc oxide the mole the weight of zinc oxide, when we figure that out is, well, the mass is 81.38 grams. So when we work that out, the moles is 2.2487⋅10-4 moles. So then that's going to give us our moles over liters. R is our gas constant, which we don't have to do anything, we just have to plug it in. And then our temperature needs to be in Kelvin, so add 273.15 to this number here and that gives us 299.15 Kelvin. So then what cancels out? Kelvins cancel out, moles cancel out, liters cancel out, and we're left with atmospheres at the end. So when we plug this in, we're going to get 0.731 atmospheres as the osmotic pressure for this given solution.
The osmotic pressure of blood is 5950.8 mmHg at 41ºC. What mass of glucose, C6H12O6, is needed to prepare 5.51 L of solution. The osmotic pressure of the glucose solution is equal to the osmotic pressure of blood.
The osmotic pressure of a solution containing 7.0 g of insulin per liter is 23 torr at 25ºC. What is the molar mass of insulin? (1 atm = 760 torr)