Find concentration of sample #4 that is a sample of 5ml of stock solution that h

Question

Find concentration of sample #4 that is a sample of 5ml of stock solution that has concentration of 251.2 mg/L diluted to 100ml total (solute+solvent)

Find concentration of sample #2 that is a sample of 2ml of stock solution that has concentration of 251.2 mg/L diluted to 100ml total (solute+solvent)

Find concentration of sample #3 that is a sample of 3ml of stock solution that has concentration of 251.2 mg/L diluted to 100ml total (solute+solvent)

Find concentration of sample #1 that is a sample of 1ml of stock solution that has concentration of 251.2 mg/L diluted to 100ml total (solute+solvent)

please show work for each sample

Part 1: Data for Calibration Curve tion of Stock Solution. 251 2 malL b. Volume of first Stock solution taken... d0m ioomL 2.00 ml Total volume on dilution Standard Sample #1.................. c. Volume of second Stock solution taken. Total volume on dilution Standard Sample #2 d. Volume of third Stock solution taken. 100ml 3.00 00 5.00 m L Total volume on dilution Standard Sample #3 e. Volume of fourth Stock solution taken..... Total volume on dilution Standard Sample #4 100 m f. Concentration of Standard Sample #1 Concentration of Standard Sample #2 Concentration ofStandard Sample #3 Concentration of Standard Sample #4 Calculations (show work for Standard Sample #1 )

Explanation / Answer

You just have to make "dilution calculation"

Molarity 1 * Volume 1 = Molarity 2 * Volume 2

a) For the first sample 1 ml originally taken

M1 = 251.2 mg/L, V1 = 1 ml

M2 = ? , V2 = 100 ml

251.2 * 1 = M2 * 100

M2 = 251.2 / 100 = 2.512 mg / L

b) for sample 2, you take 2 ml

M1 = 251.2 mg/L

V1 = 2 ml

M2 = ?

V2 = 100 ml

M1 * V1 = M2 * V2

251.2 * 2 = M2 * 100

M2 = 251.2 * 2 / 100 = 5.024 mg / L (you can also take Molarity from solution 1 and multiply that value by 2)

c)for solution of 3 ml taken

M1 = 251.2 mg/L, V1 = 3 ml

M2 = ? , V2 = 100 ml

251.2 * 3 = M2 * 100

M2 = 251.2 * 3 / 100 = 7.536 mg / L

c) for solution of 5 ml

M1 = 251.2 mg/L, V1 = 5 ml

M2 = ? , V2 = 100 ml

251.2 * 5 = M2 * 100

M2 = 251.2 * 5 / 100 = 12.56 mg / L

As I said before you can just take the concentration of sample with 1 ml and multiply it by 2, 3 and 5, you should get the same results.

Note: when making dilution calculations you must make sure you have the same units on every side of the equation

M1 * V1 = M2 * V2, that´s why I used ml instead of Liters, because we had ml on each side of the equation, you can use ml, Liters, dl, m3,, whatever you want but you must make sure you have the same units on each side

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