Question

Suppose you are titrating an acid of unknown concentration with a standardized base. At the beginning of the titration, you read the base titrant volume as 2.04 mL. After running the titration and reaching the endpoint, you read the base titrant volume as 20.95 mL.

1. What volume, in mL, of base was required for the titration?
2.Calculate the mass percent of a vinegar solution with a total mass of 96.92 g that contains 2.28 g of acetic acid.

Answer 1

1) 18.91 mL

2) 2.35 %

Step-by-step explanation:

1. The volume of base that was required is equal to the difference between the reading at the end of the titration and the reading at the beginning:

• V = 20.95 mL - 2.04 mL = 18.91 mL

2. The mass percent can be written as:

• Mass Percent = Mass solute / Total mass * 100%

For this problem:

• Mass solute = 2.28 g

• Total mass = 96.92 g

We input the data and calculate the mass percent:

• % mass = 2.28/96.92 * 100% = 2.35 %