anonymous
  • anonymous
For the titration of 25.0mL of 0.20M hydrofluoric acid with 0.20M NaOH, determine the volume of base added when pH is (a)2.85 (b)3.15 (c)11.89?
Chemistry
  • Stacey Warren - Expert brainly.com
Hey! We 've verified this expert answer for you, click below to unlock the details :)
SOLVED
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
katieb
  • katieb
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
anonymous
  • anonymous
can i tell you for the first part only? and you can solve the same way for the next parts?
anonymous
  • anonymous
tell me how i can approach all 3
anonymous
  • anonymous
ok.. dude! wait!

Looking for something else?

Not the answer you are looking for? Search for more explanations.

More answers

anonymous
  • anonymous
first part : pH = 2.85 i.e. -log(H+) = 2.85. so, [H+] = 1.4*10^-3 this is the resultant [H+] ion concentration.. by mixing 0.025L of HF and say V litres of NaOH. so. the resultant number of moles of H+ = concentration * volume = 1.4*10^-3 *(0.025 +V) and, HF dissociates as:- \[HF \leftarrow \rightarrow H ^{+}+F ^{-}\] 0.2 0 0 ...............(initially) 0.2-X x x ..................(at time t) and we know, \[K _{a}(HF) = \frac{ x ^{2} }{ 0.2-x }\] Ka(HF) = 3.47 *10^-4 solving this for x, we get x = 0.00816. thus, [H+] = x = 8.16*10^-3 NUMBER OF MOLES OF H+ FROM ACID = CONC. * VOLUME 8.16*10^-3 * 0.025 = 2.04*10^-4 number of moles of OH- = conc. of base * volume taken = 0.2*V as this no. of moles of OH- react with H+ , we will subtract this 0.2V from 2.04*10^-4 and put it equal to 1.4*10^-3(0.025+V) solving this for V, you will get the answer. i.e. you need to solve the equation. 2.04*10^-4 - 0.2V = 1.4*10^-3 ( 0.025 + V) the ans. will come out to be 8.3 *10^-4 Litres.. i think
anonymous
  • anonymous
see if this helps.
anonymous
  • anonymous
for first part ans = 0.837 mL for seconddd part ans == 0.928 mL third padrt 1.02 ml are these the answers?????????????????
anonymous
  • anonymous
are these the answers?

Looking for something else?

Not the answer you are looking for? Search for more explanations.