For a solution of 3.3 M H2CO3 (Ka = 4.4 × 10-7), calculate:
(a) [H+] ____?______M
(b) pH _____??______
(c) percent ionization ______?______%
I don't think it wise to write the Ka for H2cO3 as 4.4E-7 because it has TWO ionization constants. It is correct to write k1 = 4.4E-7.
...........H2CO3 ==> H^+ + HCO3^-
I.........3.3M.......0.......0
C.........-x.........x.......x
E.........3.3-x.......x......x
k1 = 4.4E-7 = (H^+)(HCO3^-)/(H2CO3)
Substitute into k1 exprsession and solve for x = (H^+) and convert that to pH.
% ion = [(H^+)/(H2CO3)]*100 = ?
To calculate the values of [H+], pH, and percent ionization for a solution of 3.3 M H2CO3 (Ka = 4.4 × 10-7), we will need to use the Henderson-Hasselbalch equation and the expression for percent ionization.
(a) [H+] can be calculated by using the concentration of the acid, H2CO3, and the equilibrium constant, Ka. The Ka expression for H2CO3 is:
Ka = [H+][HCO3-] / [H2CO3]
Since H2CO3 ionizes into H+ and HCO3-, we can assume that the concentration of HCO3- is equal to the concentration of [H+]. Therefore, the equation becomes:
Ka = [H+]^2 / [H2CO3]
Plugging in the values gives us:
4.4 × 10-7 = [H+]^2 / 3.3
To solve for [H+], rearrange the equation:
[H+]^2 = 4.4 × 10-7 * 3.3
Taking the square root of both sides gives us:
[H+] = sqrt(4.4 × 10-7 * 3.3)
Now you can calculate the value of [H+].
(b) pH can be calculated using the formula:
pH = -log[H+]
Substitute the value of [H+] that you obtained in part (a) into the equation to calculate the pH.
(c) Percent ionization can be calculated using the formula:
Percent ionization = ([H+]/[H2CO3]) * 100
Using the concentration values of [H+] and [H2CO3] that you obtained in part (a), plug them into the equation to calculate the percent ionization.