CEM 142

Yup, they are already up. You’re welcome.

Have a nice life!!

4 component separation

Look familiar? You are test driving an expansion on the experiment. Your reward? Tie-dye the following week. PRE-LAB QUESTIONS NEED NOT BE DONE FOR THIS LABThey are there, just ignore them

Previous:

Permanganate titrations

Thermodynamics of Calcium Hydroxide

Another Doc Ott original. seriously.
The pre-lab queastion:
We are going to try ot determine the Ksp of lead (II) iodide, by adding a KI solution drop by drop to a a solution of lead (II) nitrate until a precipitate just ‘remains’ (thereby making a saturated solution) Knowing the V (and hence concentration) of each solution at that magic point, we can determine the concentrations at equilibirum (with the solid) which allows us to calc Ksp.
10.00 mL of 0.020 M solution of lead nitrate is made. It takes exactly 0.350 mL of a 0.020 M potasium iodide solution to give ‘permenant’ precipitation. Calculate Ksp of lead iodide.
LAB REPORT: consists of short form memo Procedure, results, commentary and attachments. Make sure you report, Ave Ksp, S.D. of Ksp, as well as % error (between your ave and the real answer
Hydrolysis and Buffers

Experimentally detetermined K

T rate dependance

Crystal Violet

FP depression

VP of water
Acid in soda

This might help with what we talked about Tues (and will finish discussing wed)

Mechanisms

As I told you this week in lab, one of my goals is to slowly find websites that explain concepts both well and different from the way I teach. I am looking for short, sweet, to the point types of explanations, not just online text (read: LONG boring) versions.

With that in mind, I give you just such a set, three (each short) pages introducing equilibrium. I would love to hear any comments you have in these links, good, bad, or indifferent.
Equilibrium pt 1 Pt 2 Pt 3

Problem set

Slideshare:

If you would like me to respond to e-mail, you need to have a little bit of etiquette. The most obvious is to indicate who you are. I do not memorize your email address, so I cannot recognize thedudeman99@whatever.com as you. Pretend this like a semi formal letter. All you have to do in mention your name.

Some professionalism is appropriate. I am not your buddy who you send email jokes too. I am your college chemistry professor. No need to send me some cool chemistry joke you got from a friend. Trust me, I saw it long before you did.

I just thought of this recently. Consider it a good ‘procedure’ for doing any type of equilibrium calculation.
1. What is in the system?
2. What does it do? Write the appropriate equilbrium equation and K expression.
3. What are the initial conditions? If you don’t know them, pick a variable.
4. Which way did it shift, by how much?
5. What are the final conditions? What do you know about them?
6. Answer the question posed.

I was surfing around and found a bunch of good questions, that are complete with worked out (and explained) solutions.
Equilibrium Problems
Why should I make screencasts if you have sites like this?