Ask Question
6 December, 20:56

Codeine (c18h21no3) is a weak organic base. a 5.0 x 10-3 m solution of codeine has a ph of 9.95. what is the pkb for this base

+1
Answers (1)
  1. 6 December, 21:11
    0
    Answer is: pKb for codeine is 5,8.

    Chemical reaction: C₁₈H₂₁NO₃ + H₂O ⇄ C₁₈H₂₁NO₃H⁺ + OH⁻.

    c (C₁₈H₂₁NO₃) = 5·10⁻³ M = 0,005 mol/L.

    pH = 9,95.

    pOH = 14 - 9,95 = 4,05.

    [OH⁻] = 10∧ (-4,05) = 0,000089 mol/L.

    [OH⁻] = [C₁₈H₂₁NO₃H⁺] = 8,9·10⁻⁵ mol/L.

    [C₁₈H₂₁NO₃] = 0,005 mol/L - 0,000089 mol/L = 0,004911 mol/L.

    Kb = [OH⁻] · [C₁₈H₂₁NO₃H⁺] / [C₁₈H₂₁NO₃].

    Kb = (0,000089 mol/L) ² / 0,004911 mol/L = 1,613·10⁻⁶.

    pKb = - log (1,613·10⁻⁶) = 5,8.
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “Codeine (c18h21no3) is a weak organic base. a 5.0 x 10-3 m solution of codeine has a ph of 9.95. what is the pkb for this base ...” in 📗 Chemistry if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers