Question

In: Chemistry

Oxalic acid , HOOCCOOH (aq) , is a diprotic acid with Ka1= 0.056 and Ka2=1.5x10-4. Determine...

Oxalic acid , HOOCCOOH (aq) , is a diprotic acid with Ka1= 0.056 and Ka2=1.5x10-4. Determine the pH of a 0.12 M oxalic acid solution.

HOOCCOOH(aq) = HOOCCOO-(aq) +

H+(aq) HOOCCOO-(aq) = -OOCCOO-(aq) + H+(aq)

Expert Solution

H2C2O4 ---------------------> HC2O4- + H+

0.12 0 0

0.12 - x x x

Ka1 = x^2 / 0.12 - x

0.056 = x^2 / 0.12 - x

x = 0.0586

[H+] = 0.0586 M

HC2O4- ------------------> C2O42- + H+

0.0586 0 0.0586

0.0586 - x x 0.0586 + x

Ka2 = x * (0.0586 + x) / (0.0596 - x)

1.5 x 10^-4 = 0.0586 x + x^2 / 0.0586 - x

8.79 x 10^-6 - 1.5 x 10^-4 x = 0.0586 x + x^2

x^2 + 0.05875x - 8.79 x 10^-6 = 0

x = 1.49 x 10^-4

[H+] = 1.49 x 10^-4 M

total [H+] = 0.0586 + 1.49 x 10^-4 = 0.0588 M

pH = -log [H+] = -log (0.0588)

pH = 1.23

queen_honey_blossom answered 2 years ago

Oxalic acid , HOOCCOOH, is a diprotic acid with Ka1= 0.056 and Ka2=1.5x10-4. Determine the equilibrium...

Oxalic acid , HOOCCOOH, is a diprotic acid with Ka1= 0.056 and Ka2=1.5x10-4. Determine the equilibrium [HOOCCOOH] in a solution with an initial concentration of 0.116 M oxalic acid . HOOCCOOH = HOOCCOO- + H+ HOOCCOO- = -OOCCOO- + H+

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 2.40× 10–4 and Ka2 =...

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 2.40× 10–4 and Ka2 = 2.70× 10–12. Calculate the pH and molar concentrations of H2A, HA–, and A2– at equilibrium for each of the solutions below. .185M solution of NaHA .185M solution of Na2A

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 1.63× 10–4 and Ka2 =...

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 1.63× 10–4 and Ka2 = 4.71× 10–11. Calculate the pH and molar concentrations of H2A, HA–, and A2– at equilibrium for each of the solutions below. (a) a 0.184 M solution of H2A (b) a 0.184 M solution of NaHA (c) a 0.184 M solution of Na2A

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 3.66× 10–4 and Ka2 =...

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 3.66× 10–4 and Ka2 = 4.99× 10–12. Calculate the pH and molar concentrations of H2A, HA–, and A2– at equilibrium for each of the solutions below. (a) a 0.121 M solution of H2A pH = ? [H2A]=? [HA-]=? [A2-]=? (b) a 0.121 M solution of NaHA pH = ? [H2A]=? [HA-]=? [A2-]=? (c) a 0.121 M solution of Na2A pH = ? [H2A]=? [HA-]=? [A2-]=?

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 3.94× 10–4 and Ka2 =...

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 3.94× 10–4 and Ka2 = 2.17× 10–12. Calculate the pH and molar concentrations of H2A, HA–, and A2– at equilibrium for each of the solutions below. (a) a 0.147 M solution of H2A (b) a 0.147 M solution of NaHA

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 3.61× 10–4 and Ka2 =...

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 3.61× 10–4 and Ka2 = 4.02× 10–12. Calculate the pH and molar concentrations of H2A, HA–, and A2– at equilibrium for each of the solutions below. (a) a 0.124 M solution of H2A pH [H2A] [HA-] [A2-] (b) a 0.124 M solution of NaHA pH [H2A] [HA-] [A2-] (c) a 0.124 M solution of Na2A pH [H2A] [HA-] [A2-]

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 1.56× 10–4 and Ka2 =...

A diprotic acid, H2A, has acid dissociation constants of Ka1 = 1.56× 10–4 and Ka2 = 2.28× 10–12. Calculate the pH and molar concentrations of H2A, HA–, and A2– at equilibrium for each of the solutions below. (a) a 0.203 M solution of H2A (b) a 0.203 M solution of NaHA (c) a 0.203 M solution of Na2A

Given a diprotic acid, H2A, with two ionization constants of Ka1 = 4.08× 10–4 and Ka2...

Given a diprotic acid, H2A, with two ionization constants of Ka1 = 4.08× 10–4 and Ka2 = 2.89× 10–12, calculate the pH and molar concentrations of H2A, HA–, and A2– for each of the solutions below. (a) a 0.167 M solution of H2A (b) a 0.167 M solution of NaHA (c) a 0.167 M solution of Na2A

Glutamine (HQ) is a diprotic amino acid with Ka1=6.5x10^-3 and Ka2=1.00x10^-9. Determine the pH of the...

Glutamine (HQ) is a diprotic amino acid with Ka1=6.5x10^-3 and Ka2=1.00x10^-9. Determine the pH of the following solutions. A) 0.298 M glutamine hydrochloride (H2Q+ Cl-) B) 0.298 M glutamine (HQ) C) 0.298 M sodium glutaminate (Na+Q-)

For the diprotic weak acid H2A, Ka1 = 3.2 × 10^-6 and Ka2 = 8.0 ×...

For the diprotic weak acid H2A, Ka1 = 3.2 × 10^-6 and Ka2 = 8.0 × 10^-9. What is the pH of a 0.0600 M solution of H2A? What are the equilibrium concentrations of H2A and A2– in this solution? Please show work.