How would you prepare a 250 mL solution of 0.45 M from a stock solution of 5.5 M?
I answered this below.
mL x M = mL x M.
Thank you very much
112.5
To prepare a 250 mL solution of 0.45 M from a stock solution of 5.5 M, you need to dilute the stock solution with the appropriate amount of solvent (usually water).
Here's how you can calculate the amount of stock solution and solvent needed:
1. Use the dilution equation: C1V1 = C2V2
C1 = initial concentration (stock solution concentration) = 5.5 M
V1 = initial volume (unknown)
C2 = final concentration (desired concentration of the diluted solution) = 0.45 M
V2 = final volume = 250 mL
2. Rearrange the equation to solve for V1:
V1 = (C2 * V2) / C1
V1 = (0.45 M * 250 mL) / 5.5 M
V1 = 11.36 mL (rounded to two decimal places)
3. Calculate the volume of solvent (water) needed to make up the final volume:
Volume of solvent = V2 - V1
Volume of solvent = 250 mL - 11.36 mL ≈ 238.64 mL
So, you would need to measure 11.36 mL of the stock solution and add approximately 238.64 mL of solvent (water) to prepare a 250 mL solution with a concentration of 0.45 M.