January 15, 2025, 11:45:16 PM
Forum Rules: Read This Before Posting


« previous next »
Pages: [1]   Go Down

Topic: Weak Acid plus Strong Base pH  (Read 5090 times)

0 Members and 1 Guest are viewing this topic.

Offline yankeekd25

  • Regular Member
  • ***
  • Posts: 23
  • Mole Snacks: +0/-0
Weak Acid plus Strong Base pH
« on: March 29, 2009, 09:00:55 PM »
An aqueous solution contains 0.434 M hydrocyanic acid.

Calculate the pH of the solution after the addition of 3.20E-2 moles of sodium hydroxide to 150 mL of this solution.
(Assume that the volume does not change upon adding sodium hydroxide).

Ka for HCN= 4.0 x 10^-10

Doesn't the concentration of the conjugate base need to be given in order to solve this?
Logged

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27895
  • Mole Snacks: +1816/-412
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: Weak Acid plus Strong Base pH
« Reply #1 on: March 30, 2009, 03:34:30 AM »
Quote from: yankeekd25 on March 29, 2009, 09:00:55 PM
Doesn't the concentration of the conjugate base need to be given in order to solve this?

You have to calculate it. Assume neutralization went to completion.
Logged
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline yankeekd25

  • Regular Member
  • ***
  • Posts: 23
  • Mole Snacks: +0/-0
Re: Weak Acid plus Strong Base pH
« Reply #2 on: March 30, 2009, 08:56:43 AM »
Okay. How do you calculate it?
Logged

Offline AWK

  • Retired Staff
  • Sr. Member
  • *
  • Posts: 7976
  • Mole Snacks: +555/-93
  • Gender: Male
Re: Weak Acid plus Strong Base pH
« Reply #3 on: March 30, 2009, 11:03:12 AM »
Start from a balanced equation of neutralization
Logged
AWK
Pages: [1]   Go Up
« previous next »
Sponsored Links