Tuesday, April 12

Today in class we continued to learn about equilibrium constant expressions. Yesterday we learned how to create Kp expressions, and today we finished learning about Kc expressions. We flipped our packets to page 12 and we worked through the page. To form a Kc expression, I will use letter c on page 12 as an example.

c. HF(aq) + H2O(l) <--> H3O+(aq) + F-(aq)

First we get rid of any substances that aren't gases or aqueous solutions. That would mean getting rid of H20(l). So now we have

HF(aq) <--> H3O+(aq) + F-(aq)

So now taking this, we place it into he equation for the Kc.


[F-] * [H3O+]
Kc = _______________

[HF]

And that is our Kc value.

I found this picture that shows the value of the Kc.

We moved in class, and added math to Kc and Kp. The only thing we changed from before, is that now the values have numbers to them. Using our knowledge of math, we plugged the equations into our calculators and got our answers. The answers o #'s 4-7 on page 13 are as follows.
4. .222
5. .00379
6. 4.315
7. .025

The next thing we did in class, was doing algebra with the constants of equilibrium. We took our equation as shown above, and we plugged in values and solved for the values we didn't have. The answers for page 14 #'s 9 and 10 are as follows.
9. 4.25 * 10^-4
10. 2.6377

Mr. H then told us that we have a quiz tommorow, and that he won't be tellling us about quizzes ahead of time from now on because we stress out less if we don't worry about it. He said we would finish the day with jokes from his jokebook, but we didn't have time. Maybe tomorrow?