Question

We prepare a 0.1M solution of a weak electrolyte with i = 3 Given that the degree of dissociation of the electrolyte is 95%, calculate the osmotic pressure of the solution at 298K.

Answer 1

298K

Step-by-step explanation:

The osmotic pressure (π) of a solution is given by the van 't Hoff equation:

π = iMRT

Where M is the molarity of the solute, i is the van 't Hoff factor (the number of ions or particles the solute dissociates into in solution), R is the gas constant, and T is the temperature in Kelvin.

For a weak electrolyte with a degree of dissociation (α) of 95%, the effective concentration of the solute is:

C_eff = C_total * α

where C_total is the initial concentration of the solution.

Since the concentration of the solution is 0.1 M, the effective concentration of the solute is:

C_eff = 0.1 M * 0.95 = 0.095 M

The van 't Hoff factor for a weak electrolyte is given by:

i = 1 + α

Substituting the value of α into the equation, we get:

i = 1 + 0.95 = 1.95

Substituting the values of i, M, R, and T into the van 't Hoff equation, we get:

π = (1.95)(0.095 M)(0.08206 L·atm/(mol·K))(298 K) = 4.02 atm

Therefore, the osmotic pressure of the solution is 4.02 atm at 298K

Answer 2

We can use the van 't Hoff factor to calculate the osmotic pressure of the solution. The van 't Hoff factor (i) is a measure of the number of particles into which a solute dissociates in solution. For a weak electrolyte, the van 't Hoff factor is equal to the degree of dissociation (α). In this case, i = 3 and α = 0.95. The osmotic pressure (π) can be calculated using the formula π = iMRT, where M is the molarity of the solution, R is the gas constant (0.08206 L-atm/mol-K), and T is the temperature in Kelvin (298 K). Substituting the values, we get π = 3 x 0.1 M x 0.08206 L-atm/mol-K x 298 K = 7.66 atm.

Therefore, the osmotic pressure of the solution is 7.66 atm.