Question

The volume (in mL) required to prepare 350 mL of 1X buffer solution from a fifty times (50X) concentrated buffer stock solution is ..........

Hint:

To dilute a concentrated solution, use the dilution equation \( C_1 V_1 = C_2 V_2 \) to calculate the required volume of stock solution.

Answer 1

Correct Answer: 7

Step 1: Use the dilution equation.
The dilution equation is given by: \[ C_1 V_1 = C_2 V_2, \] where \( C_1 \) and \( C_2 \) are the concentrations of the stock and the final solution, and \( V_1 \) and \( V_2 \) are the volumes of the stock and final solution, respectively.

Step 2: Substituting the known values.
- \( C_1 = 50X \) (concentrated solution) - \( C_2 = 1X \) (final solution) - \( V_2 = 350 \, \text{mL} \) (final volume) \[ 50X \times V_1 = 1X \times 350 \, \text{mL}, \] \[ V_1 = \frac{350}{50} = 7 \, \text{mL}. \]

Step 3: Conclusion.
The required volume of the concentrated buffer stock solution is \( \boxed{7} \, \text{mL} \).