Calculate the degree of ionization of acetic acid in solution 1 through 3?
All I am giving is the pH...
pH of solution 1= 3
pH of solution 2= 3.5
pH of solution 3= 5
Then, I did this...
HC2H3O2 (aq) + H2O (l) equals H3O+ (aq) + C2H3O2- (aq)
Ka= 1.7 E -5 (according to chart in my book)
Ka= {H3O}{C2H3O2)/{HC2H3O2}=1.7 E -5
How do I figure the degree of ionization for solutions 1-3 from what I am given above? Any help would be greatly appreciated.
Nevermind. I got it. It would help if I looked at the concentration data that my lab book gives me complete the problem:)
1.75 x 10^-5=Ka= {H3O}{C2H3O2)/{HC2H3O2}
lets do the first one,
HC2H3O2 + H2O----> H3O+ + C2H3O2-
pH=3, so
H3O+=10^-(3)=1 x 10 ^-3 M
so the ratio of H3O+= C2H3O2-
So, Ka=1.75 x 10^-5= {H3O}{C2H3O2)/{HC2H3O2}
becomes
Ka=1.75 x 10^-5= [1 x 10 ^-3 M][1 x 10 ^-3 M]/{HC2H3O2},
solve for the molarity of HC2H3O2
1.75 x 10^-5/(1 x 10^-3)^2=HC2H3O2
(H3O+/HC2H3O2)*100, should give you the degree of ionization
Good to know.
Because the part should be,
(1 x 10^-3)^2/1.75 x 10^-5=HC2H3O2
(H3O+/HC2H3O2)*100, should give you the degree of ionization
Flipped it by accident.
To calculate the degree of ionization of acetic acid in each solution, you can use the given pH values and the Ka value of acetic acid.
The Ka value represents the equilibrium constant for the ionization of acetic acid in water. It is defined as the ratio of the concentrations of the dissociated ions (H3O+ and C2H3O2-) to the concentration of the undissociated acid (HC2H3O2).
The general equation for degree of ionization (α) is:
α = [H3O+] / [HC2H3O2]
Let's calculate the degree of ionization for each solution:
Solution 1:
Given pH = 3
[H3O+] = 10^(-pH) = 10^(-3) = 0.001 M
Plugging this value into the equation for α:
α = [H3O+] / [HC2H3O2] = 0.001 M / [HC2H3O2]
Solution 2:
Given pH = 3.5
[H3O+] = 10^(-pH) = 10^(-3.5) = 0.000316 M
Plugging this value into the equation for α:
α = [H3O+] / [HC2H3O2] = 0.000316 M / [HC2H3O2]
Solution 3:
Given pH = 5
[H3O+] = 10^(-pH) = 10^(-5) = 0.00001 M
Plugging this value into the equation for α:
α = [H3O+] / [HC2H3O2] = 0.00001 M / [HC2H3O2]
So, the degree of ionization for each solution is given by the ratio of the concentration of H3O+ to the concentration of HC2H3O2. However, to determine the exact value of α, we need to know the initial concentration of acetic acid ([HC2H3O2]) in each solution.