### Determining the pOH of a Hydrocyanic Acid Solution**Problem Statement:**Hydrocyanic acid (HCN) has a \( K_a \) value of \( 4.9 \times 10^{-10} \). If the initial concentration of HCN is 0.432 M, determine the pOH of this solution at equilibrium.---**Solution Steps:**1. **Write the ionization equation for HCN:** \[ \text{HCN} \, \rightleftharpoons \, \text{H}^+ + \text{CN}^- \]2. **Set up the expression for the acid dissociation constant \( K_a \):** \[ K_a = \frac{[\text{H}^+][\text{CN}^-]}{[\text{HCN}]} \] Given \( K_a = 4.9 \times 10^{-10} \) and initial [HCN] = 0.432 M.3. **Assume \( x \) is the concentration of \( \text{H}^+ \) and \( \text{CN}^- \) at equilibrium:** \[ K_a = \frac{x^2}{0.432 - x} \approx \frac{x^2}{0.432} \]4. **Solve for \( x \):** \[ x^2 = 4.9 \times 10^{-10} \times 0.432 \] Calculate \( x \), which represents \( [\text{H}^+] \).5. **Calculate the pH:** \[ \text{pH} = -\log[\text{H}^+] \]6. **Find pOH using the relation:** \[ \text{pOH} = 14 - \text{pH} \]This step-by-step guide helps in determining the equilibrium pOH of a weak acid solution using its dissociation constant and initial concentration.

For a weak acid: [H+] = (Ka x C)1/2 Where, C = molar concentration of acid pH = -log[H+] pOH = 14 -…

Answered: Hydrocyanic acid has a Ka value of 4.9…

Hydrocyanic acid has a Ka value of 4.9 x 10-10. If the initial concentration of HCN is 0.432 M determine the pOH of this solution at equilibrium.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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