 ## GOB Chemistry

Learn the toughest concepts covered in your GOB - General, Organic, and Biological Chemistry class with step-by-step video tutorials and practice problems.

Osmotic Pressure is the force that drives Osmosis from higher concentration to lower concentration.

Osmotic Pressure Calculations
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concept

## Osmotic Pressure Concept 1 1m
Play a video:
now recall the 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 the osmotic pressure which is represented by this piloting symbol is in units of atmospheres and it equals I. Which is your van Hoff factor, capital M. Which is your molar itty or concentration or so liability. Okay. And that will be in moles per liter. So moles aside over leaders of solution Times, are are is your gas constant which is .08-06. Leaders 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.
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example

## Osmotic Pressure Example 1 1m
Play a video:
here. It says calculate the osmotic pressure of the solution that is 18.30 mg of zinc oxide in 15.1 mls of solution at 26 degrees Celsius. Alright, so osmotic pressure equals I times polarity times are times T zinc oxide is an ionic solute that breaks up into zinc ion and oxide island. That's two ions. So I equals two capital M. Is our polarity which is moles over leaders here. When I convert the 15 mls into leaders, that's 150.15 liters, Then I can change the 8.30 mg of zinc into moles. So remember, one mg is 10 to the negative three g And one mole of zinc. The weight of zinc oxide, the mole, the weight of zinc oxide. When we figure that out is Well the masses 81 38 g. So when we work that out, the moles is 2.2487 times 10 to the minus four moles. So then that's gonna give us our moles over leaders. Or 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 to 73.15 to this number here, and that gives us 2 99.15 Kelvin. So then what cancels out Calvin's, cancel out moles, cancel out leaders, cancel out and we're left with atmospheres at the end. So we plug this in. We're gonna get as our atmosphere's . atmospheres as the osmotic pressure for this given solution.
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Problem

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.

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Problem

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) 