Question

CHM 202 F 19 HW 10 culate the (H). (HSO4)- and ISO 21 - jon concentrations and the pH of a 0.050 M H2SO4. Kalis very large and Kis 0.012. 2. Show how methylamine, CH NH dissociates in solution and calculate the pH of a 0.25M aqueous solution of the substance. Ky for CH3NH2 is 1.8 x 10-4 3. Write a balanced equation to show how the following ions hydrolyze in water and write the acid or base dissociation constant for each:. d) CH:CO2 d0 HCM a) CN b) A1+ c) CO;2-

mistake

Answer 1

Answer 1

As Ka for first dissociation of H₂SO₄ is very large,

So, [HSO₄^-] = [H₃O⁺] = 0.050 M

Now, second dissociation occurs as:

On solving the quadratic equation,

4sou tho - Hot & sour Ka 20.012 Assuming & moles of esou dissociation, ICE is. 4sou thot sou²- Initial 0.050 0.050 Change + x + x Equilibrium 0.050-x 0.050 tx x K = 0.012 = (0.050+2 ) & (0.050 -2) 0.0006 - 0.0l2x = 0.050x tx² x² +0.062x - 0.0006 zo

x = 0.00851 M

So, final concentrations are as :

[HSO₃^-] = 0.050 - 0.00851 = 0.00415 M

[H₃O⁺] = 0.050 + 0.00851 = 0.0585 M

[SO₄^2-] = 0.00851 M