Ask Question
Today, 05:52

A buffer solution has 0.625 M HCN and 0.575 M CN-. If 0.030 moles of NaOH is added to 400. mL of the buffer solution, what is the pH after the addition? The pKa of hydrocyanic acid is 9.31.

+1
Answers (1)
  1. Today, 08:32
    0
    pH = 9.393

    Explanation:

    Give that 400mL buffer 1L = 1000mL 0.625 mol of HCN solution = 0.250 mol HCN

    Therefore,

    400mL buffer solution 1L = 1000mL 0.575 mol CN^ - solution = 0.230 mol of CN^-

    Pka HCN = 9.31

    Therefore, to get ph:

    pH = 9.32 + log (0.230 mol + 0.030 mol) / (0.250 mol - 0.030 mol)

    pH = 9.32 + 0.0726

    pH = 9.393
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “A buffer solution has 0.625 M HCN and 0.575 M CN-. If 0.030 moles of NaOH is added to 400. mL of the buffer solution, what is the pH after ...” in 📘 Chemistry if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers