Step 1: Identify the formula for molarity (M) in terms of osmotic pressure (π), the gas constant (R), and temperature (T). The formula is M = π / (RT).
Step 2: Plug in the values for osmotic pressure (π = 3.0 atm), gas constant (R = 0.0821 L atm/(K mol)), and temperature (T = 298 K) into the formula.
Step 3: Calculate the denominator (RT) by multiplying R and T: 0.0821 * 298.
Step 4: Perform the multiplication: 0.0821 * 298 = 24.4758.
Step 5: Now divide the osmotic pressure (3.0 atm) by the result from Step 4 (24.4758): 3.0 / 24.4758.
Step 6: Perform the division to find the molarity: 3.0 / 24.4758 = 0.1225.
Step 7: Round the result to two decimal places to get the final molarity: 0.12 M.