Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

HCl ionizes completely in water. What is the [H^+] and [OH^-] of a 0.01 M soluti

ID: 86092 • Letter: H

Question

HCl ionizes completely in water. What is the [H^+] and [OH^-] of a 0.01 M solution of HCl? What is the pH? Assuming 10% ionization, what is the [H^+] and [OH^-] of a 0.01 M solution of H_2 CO_3? What is the pH? Is the hydrogen ion concentration of a pH 3.8 solution higher or lower than that of a solution with a pH of 6.2? If solution A contains 1 times 10^-6 M H^+ ions and solution B contains 1 times 10^-8 M H^+ ions, which solution is more acidic? Make a statement relating hydrogen ion concentration to the acidity of a solution. Make a statement relating hydrogen ion concentration to the basicity of a solution. HA is an acid that ionizes 10% in solution. What is the [H^+] of a 0.01 M solution of HA? What is its pH? Write the equation for the neutralization of KOH by HCl.

Explanation / Answer

1. pH = -log (H+) = -log (0.01) = 2    H+ ions = 10-2            H+ + OH- = 10-14

OH- conc = 10-12

2. H2CO3 + H2O - HCO-3 + H3O+
     H3O+ = 0.1 * 0.001M = 0.0001M

pH = -log (H3O+) = -log (0.0001) = 4    H+ ions = 10-4

OH- conc = 10-8

3. Higher. Hydrogen ion conc higher if acidity is high.

4. Solution A is more acidic. 10-6 H+ ions > 10-8 H+ ions

5. Larger the concentration of hydrogen ions, the more acidic the solution.

6. Lower the concentration of hydrogen ions, the more basic the solution.

7. H+ 0.01M in that only 10% undergoes ionisation.
H+ = 0.1 * 0.01M = 0.001M

pH = -log (H+) = -log (0.001) = 3

8. HCL + KOH ----- KCl + H2O