science

posted by .

What fraction of piperazine (perhydro-1,4-diazine) is in each of its three forms (H2A, HA–, A2–) at pH 8.67? The acid dissociation constant values for piperazine are Ka1 = 4.65×10–6 and Ka2 = 1.86×10–10.

• science -

You do these using the alpha system.
The denominator of the fraction is
D = (H^+)^2 + k1*(H^+) + k1k1

alphao = (H2A) = (H^+)^2/D
alpha1 = (HA^-) = k1*(H^+)/D
alpha2 = (A^2-) = k1k2/D
Plug in the numbers and solve.

• science -

THIS IS WRONG. DR. BOB IS WRONG YET AGAIN. DON'T WASTE YOUR TIME LOOKING AT THIS.

Similar Questions

1. Chemistry

Given a diprotic acid, H2A, with two ionization constants of Ka1 = 3.9× 10–2 and Ka2 = 5.9× 10–8. Calculate the pH and molar concentrations of each protonated form for a: (a)0.135 M solution of H2A pH= [H2A]= [HA]= [A2-]= (b)0.135 …
2. chemistry

For the diprotic weak acid H2A Ka1=2.1x10^-5 and Ka2=5.5x10^-7. What is the pH of a 0.0800M solution of H2A?
3. Analytical Chemistry

What fraction of piperazine (perhydro-1,4-diazine) is in each of its three forms (H2A, HA–, A2–) at pH 7.05?
4. Chemistry

What fraction of piperazine (perhydro-1,4-diazine) is in each of its three forms (H2A, HA–, A2–) at pH 7.22?
5. chemistry

What fraction of piperazine (perhydro-1,4-diazine) is in each of its three forms (H2A, HA–, A2–) at pH 8.98?
6. Chemistry

For the diprotic weak acid H2A, Ka1 = 2.2 × 10-5 M and Ka2 = 7.8 × 10-7 M. What is the pH of a 0.0650 M solution of H2A?
7. Chemistry

For the diprotic weak acid H2A, Ka1 = 2.2 × 10-5 M and Ka2 = 7.8 × 10-7 M. What is the pH of a 0.0650 M solution of H2A?
8. Chemistry

For the diprotic weak acid H2A, Ka1 = 2.2 × 10-5 M and Ka2 = 7.8 × 10-7 M. What is the pH of a 0.0650 M solution of H2A?
9. Chemistry

Consider a 0.10 M solution of a weak polyprotic acid (H2A) with the possible values of Ka1 and Ka2 given below, calculate the contributions to [H3O+] from each ionization step. Part 1: Ka1=1.0*10^-4 Ka2=1.0*10^-5 Part 2: Ka1=1.0*10^-4 …
10. CHEMISTRY!!

For the diprotic weak acid H2A, Ka1 = 2.0 × 10^-6 and Ka2 = 6.7 × 10^-9. What is the pH of a 0.0800 M solution of H2A?

More Similar Questions