QUESTION

NEED HELP ASAP. ONLY ANSWER IF YOU ARE SURE.

1a. You are asked to prepare a buffer solution with a total volume of 250mL. You have available to you 3.0M trifluoroacetic acid (MW: 114.02 g/mol, d = 1.49 g/mL) and sodium trifluoroacetate (MW: 136.01 g/mol). The final concentration for the acid in your buffer should be 0.4M and the final concentration for the base in your buffer solution should be 0.4M. Note: if the concentration of a component is not given, you can assume that it is a solid.

How much base do you need (in g)? Record your answer with 2 digits after the decimal point.

1b. Consider the table below. Which acid and conjugate base pair would be suitable to use for the preparation of a buffer solution with a pH of 7.07?

Acid

Ka

Conjugate Base Salt

A

Oxalic acid

5.4 x 10-2

Sodium hydrogen oxalate

B

Hydrofluoric acid

3.5 x 10-4

Sodium Fluoride

C

Carbonic acid

4.3 x 10-7

Sodium bicarbonate

D

Boric acid

7.3 x 10-10

Sodium Dihydrogen Borate

E

Disodium hydrogen phosphate

2.2 x 10-13

Trisodium phosphate

Public Answer

U2V0NX The First Answerer