Last modified: Sat 10/19/2013 04:14:29 pm
ACA

Oklahoma State University

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Answer all of the questions below. If you do not know an answer enter CNA. However, it will help me the most if you answer each question with your best intuition/idea about what would be a reasonable answer.


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Laboratory Section:

1. H2SO3(aq) is a diprotic acid. Given a 0.100 M H2SO3 solution, calculate the of [H+] and [HSO3-] produced in the first dissociation. NOTE: Ka1(H2SO3) = 1.7 x 10-2. Watch out! you will HAVE to use the quadratic equation to solve for 'x' in this problem.

a) [H+] = M

b) [HSO3-] = M

2. Calculate the of [H+] and [SO32-] in the second dissociation. NOTE: Ka2(H2SO3) = 6.4 x 10-8.

a) [H+] = M

b) [SO32-] = M

3. Which dissociation for a diprotic acid contributes the most to the [H+] in the solution, the first dissociation or the second?

4. Given 0.100 M solutions of each of the following diprotic acids order them from lowest (most acidic) to highest pH (least acidic). (NOTE: Here is a table of equilibrium constants to help answer this question.)

H2SO3 : H2S : H2SO4 : H2CO3 : H2C2O4

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5. Is there anything about the questions that you feel you do not understand? List your concerns/questions.

6. If there is one question you would like to have answered in lecture, what would that question be?