how many mL of a stock 2.50M HCI solution are required to prepare 25.mL of a 0.15M HCI solution?
Use the dilution formula.
mL1 x M1 = mL2 x M2 or if you prefer
c1v1 = c2v2 where c = concentration and v = volume.
To calculate the volume of the stock solution needed to prepare a desired concentration, you can use the formula:
C1V1 = C2V2
Where:
C1 = concentration of the stock solution (2.50 M)
V1 = volume of the stock solution needed to prepare (unknown)
C2 = desired final concentration (0.15 M)
V2 = volume of the final solution (25 mL)
Rearranging the formula, we have:
V1 = (C2 * V2) / C1
Now let's plug in the values:
V1 = (0.15 M * 25 mL) / 2.50 M
Simplifying the equation:
V1 = (0.15 * 25) / 2.50
V1 = 1.5 / 2.50
V1 = 0.6 mL
Therefore, you will need to measure 0.6 mL of the stock 2.50 M HCI solution and then add it to 24.4 mL (25 mL - 0.6 mL) of a suitable solvent to prepare 25 mL of a 0.15 M HCI solution.