How many milliliters of a 0.155 M KCl solution are required to contain 2.55 g of KCl?

• A. 250 mL
• B. 98.5 mL
• C. 165 mL
• D. 211 mL

Answer: (D)

Verified step by step guidance

1. First, calculate the number of moles of KCl present in 2.55 g. Use the molar mass of KCl, which is the sum of the atomic masses of potassium (K) and chlorine (Cl). The formula is: \(\text{moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}}\).
2. Next, use the molarity definition to relate moles of solute to volume of solution. Molarity (M) is defined as moles of solute per liter of solution: \(M = \frac{\text{moles of solute}}{\text{volume of solution in liters}}\).
3. Rearrange the molarity formula to solve for the volume of solution: \(\text{volume (L)} = \frac{\text{moles of solute}}{M}\).
4. Substitute the moles of KCl calculated in step 1 and the given molarity (0.155 M) into the rearranged formula to find the volume in liters.
5. Finally, convert the volume from liters to milliliters by multiplying by 1000, since 1 L = 1000 mL.