Question

A standard solution is prepared for the analysis of fluoxymesterone (C20H29FO3), an anabolic steroid. A stock solution is first prepared by dissolving 10.0 mg of fluoxymesterone in enough water to give a total volume of 500.0 mL. A 10.0-mL aliquot (portion) of this solution is diluted to a final volume of 100.0 mL. Calculate the concentration of the final solution in terms of molarity. x 10 M

Answer 1

Answer:

The final solution has a concentration of 5.95 * 10^-6 M

Explanation:

Step 1: data given

Mass of fluoxymesterone : 10mg = 0.01g

Molar mass of  fluoxymesterone = 336g/mole

Volume = 500 mL =0.5 L

Step 2: calculate Concentration of  fluoxymesterone

Concentration = mole / volume

⇒ To find the concentration, we first need to find the number of moles

⇒moles fluoxymesterone= mass of fluoxymesterone / Molar mass

0.01g / (336g/mole) = 2.976 *10^-5 mole

C =  2.976 *10^-5 mole / 0.5 L = 5.95 * 10 ^-5 M

Step 3: Calculate dilution

⇒ If 10 mL  is diluted to 100 ml then this is a 10x dilution (100 ml /10 ml = 10) so the final solution will be 10 x more dilute.

⇒5.95 * 10^-5 M /10  = 5.95 ^* 10^-6 M

We can control this through the following formula: M1 * V1 = M2 * V2

5.95 *10^-5 * 10 * 10 *^-3 = M2 *0.1 L

M2 = 5.95 * 10^-6 M