Calculating the Osmotic Pressure of 5% Urea Solution at 27°C

Introduction:
Osmotic pressure is the pressure required to prevent the flow of solvent molecules across a semi-permeable membrane, separating a solution from its pure solvent. It is an important parameter used to measure the concentration of solute particles in a solution.

Formula for Osmotic Pressure:
The osmotic pressure (π) of a solution can be calculated using the formula:
π = (n/V)RT

Where:
- π is the osmotic pressure
- n/V is the molar concentration of the solute
- R is the ideal gas constant (8.314 J/(mol·K))
- T is the temperature in Kelvin

Calculating Concentration (n/V):
To calculate the molar concentration of urea in the solution, we need to determine the number of moles of urea present.

Step 1: Determine the molecular weight of urea.
The molecular weight of urea (CH4N2O) is calculated by adding up the atomic weights of its constituent elements: C (12.01 g/mol), H (1.008 g/mol), N (14.01 g/mol), and O (16.00 g/mol).
Molecular weight of urea = 12.01 + 4(1.008) + 14.01 + 16.00 = 60.06 g/mol

Step 2: Calculate the mass of urea.
Given that the solution is 5% urea, we can calculate the mass of urea in the solution.
Mass of urea = 5% * Total mass of solution

Step 3: Convert mass to moles.
Using the molecular weight of urea, we can convert the mass of urea to moles.
Moles of urea = Mass of urea / Molecular weight of urea

Step 4: Calculate the molar concentration.
The molar concentration can be determined by dividing the moles of urea by the volume of the solution in liters.
Molar concentration (n/V) = Moles of urea / Volume of solution (in L)

Converting Temperature to Kelvin:
The given temperature is 27°C, which needs to be converted to Kelvin.
Temperature in Kelvin = 27°C + 273.15

Calculating Osmotic Pressure:
Now that we have the molar concentration (n/V) and the temperature (T) in Kelvin, we can use the formula to calculate the osmotic pressure (π).
π = (n/V)RT

Results:
By substituting the values into the formula, you can calculate the osmotic pressure of the 5% urea solution at 27°C. The final result will be in units of pressure (e.g., Pascal or atmospheres).

Conclusion:
The osmotic pressure of a 5% urea solution at 27°C can be calculated by determining the molar concentration of urea in the solution and using the formula π = (n/V)RT. This calculation allows us to understand the concentration of solute particles in the solution and their effect on osmotic pressure.