Question

If you want to use a serial dilution to make a 1/50 dilution. The first dilution you make is a 1/5 dilution with a total volume of 1 ml. To make that dilution you would add ______of your stock solution and______ of your solvent. Then you make a 1/10 dilution and add ______ of your first dilution and ______ of your solvent.Select one:a. 0.1 ml, 0.9 ml, 0.2 ml, 0.8 mlb. 0.3 ml, 0.7 ml, 0.1 ml, 0.9 mlc. 0.2 ml, 0.8 ml, 0.1 ml, 0.9 mld. 0.2 ml, 0.8 ml, 0.3 ml, 0.7 mle. None of these answer choice

Answer 1

Answer:

c.

Explanation:

A serial dilution is a dilution that is made fractionated. The stock solution is diluted, then this now solution is diluted, and then successively. The final dilution is the multiplication of the steps dilutions.

The representation of the dilution is v/v (volume per volume) indicates how much of the stock solution is in the total volume of the solution. So 1/5 indicates 1 mL to 5 mL of the solution. If the final volume must be 1 mL, then the stock solution must be 0.2 mL (0.2/1 = 1/5), and the volume of the solvent is 1 mL - 0.2 = 0.8 mL.

The second solution is done with a dilution of 1/10 or 1 mL of the first solution in 10 mL of the total solution. Because the solution has 1 mL, then the volume of the first solution must be 0.1 mL (0.1/1 = 1/10), and the volume of the solvent that must be added is 1 mL - 0.1 mL = 0.9 mL.