Asked by Will
Calculate the volume of .300 M NaOH needed to prepare a pH=3.50 buffer with 250ml of .075M HF solution. pKa (HF) = 3.15
Answers
Answered by
DrBob222
You have 250 mL x 0.075M = 18.75 mmoles HF.
........HF + NaOH ==> NaF + H2O
initial.18.75..0.......0......0
add.............x................
change..-x.....-x......+x.....+x
equil..18.75....0........x.....x
pH = pKa + log [(base)/(acid)]
3.50 = 3.15 + log(x/18.75-x)
Solve for x which gives millimoles, then
mmoles = mL x M
You know mmoles and M, solve for mL of the 0.3M NaOH to add.
........HF + NaOH ==> NaF + H2O
initial.18.75..0.......0......0
add.............x................
change..-x.....-x......+x.....+x
equil..18.75....0........x.....x
pH = pKa + log [(base)/(acid)]
3.50 = 3.15 + log(x/18.75-x)
Solve for x which gives millimoles, then
mmoles = mL x M
You know mmoles and M, solve for mL of the 0.3M NaOH to add.
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.