"Calculate the pH during the titration of 20.00 mL of 0.1000 M HF(aq) with 0.2000 M NaOH(aq) after 9.4 mL of the base have been added. Ka of hydrofluoric acid

Question

asked Jul 1, 2021 157k views

1 Answer

Maksym Strukov · Answer 1 · 2021-07-05T03:38:13+0000

Answer:

The answer is " 10.39"

Step-by-step explanation:

Calculating acid moles:

$= 0.02000 \ L * 0.1000 \ M \\\\= 0.002000$

Calculating NaOH moles:

$= 0.02012 \ L * 0.1000 \ M \\\\= 0.002012$

calculating excess in OH- Moles:

$= 0.002012 - 0.002000\\\\=0.000012$

calculating total volume:

$= 20.00 + 20.12\\\\ = 40.12 mL \\\\= 0.04012 L$

$[OH-]= \frac{0.000012} { 0.0472}$

=0.00025 M

$pOH = - \log 0.00025$

= 3.6

pH = 14 - pOH

= 10.39