# concentration of ion at equilibrium

Please help with the following problem. Provide step by step calculations.

Consider a solution that is 0.10 M in a weak triprotic acid that is represented by the general formula H3A with the following ionization constants:

For H3A: Ka1= 1.0 x 10 ^-3 Ka2= 1.0 x 10 ^-8 Ka3= 1.0 x 10 ^-12

What is the concentration of HA^ 2- ?

a) 4.5 x 10^-3 M

b) 1.0 x 10^-4 M

c) 3.2 x 10^-5 M

d) 1.0 x 10^-8 M

e) 6.2 x 10^-7 M

https://brainmass.com/chemistry/chemical-equilibrium/calculating-concentration-ion-equilibrium-125792

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Consider a solution that is 0.10 M in a weak triprotic acid that is represented by the general formula H3A with the following ionization constants:

For H3A: Ka1= 1.0 x 10 ^-3 Ka2= 1.0 x 10 ^-8 Ka3= 1.0 x 10 ^-12

What is the concentration of HA^ 2- ?

a) 4.5 x 10^-3 M

b) 1.0 x 10^-4 M

c) 3.2 x 10^-5 M

d) 1.0 x 10^-8 M

e) 6.2 x 10^-7 M

A triprotic acid (H3A) can undergo one, two, or three dissociations and has three dissociation ...

#### Solution Summary

It shows how to calculate the concentration of ions at equilibrium for a weak triprotic acid solution. The solution is detailed and well presented.