Final answer:
To find the osmotic pressure of a 0.0138 M KBr solution at 25 degrees Celsius, convert the temperature to Kelvins, double the molarity for the complete ionization of KBr, and apply the osmotic pressure formula Π = MRT using the ideal gas constant.
Step-by-step explanation:
To calculate the osmotic pressure of a 0.0138 M KBr solution at 25 degrees Celsius, we need to use the osmotic pressure equation Π = MRT, where Π is the osmotic pressure, M is the molarity of the solution, R is the ideal gas constant (0.0821 L·atm/K·mol), and T is the temperature in Kelvins. First, convert the temperature from Celsius to Kelvins by adding 273.15 to the Celsius temperature, which gives us 298.15 K. As KBr is a strong electrolyte that fully dissociates into two ions, K+ and Br-, the total concentration of particles in solution is double the concentration of KBr, so we have (2)(0.0138 M) = 0.0276 M.
Now we plug these values into the formula:
Π = (0.0276 mol/L) [0.0821 (L·atm)/(K·mol)] (298.15 K)
Multiply these together to find the osmotic pressure.