In the "Clueless" episode of House, Dr. House was able to prove one of his patients was being poisoned by his fiance by using a confirmation reagent. And similar to a qualitative analysis scheme, he was able to identify that gold was present on a person's hands. Similarly, chemists use a qualitative analysis scheme to identify which ions are present in a solution.
In lab next week you will be given a solution containing Ag+, Pb2+, Cu2+, Ni2+, Al3+, and Bi3+/5+. You will need to follow a scheme outlined in the manual and design your own procedure that will allow you to determine which ions are present in an unknown solution. You will have 3 lab periods to experiment and in the 4th lab period you will be given your unknown to identify.
The scheme we use to identify the ions utilizes differences in solubility and we classify the ions into groups based on their solubility. I outlined the Group I separation, which precipitates out AgCl and PbCl2.
The separations of the ions we will analyze depend on four main effects:
1. Common Ion
2. pH
3. Complex Ion Formation
4. Ampoterism
I discussed the Common Ion Effect today, as it follows Le Chatlier's Principle. I performed a few calculations illustrating the dramatic effect the Common Ion effect can have on solubility.
We will continue with pH effects on Friday and it would be good to look over the strong acids and strong bases, because you will need to know them off the top of your head.
Quote of the Day:
"Why is it so difficult to motivate ourselves when we know that results come only through motivation?'
Songs Played Before Class:
Nelly - Just A Dream
The Killers - All These Things That I've Done
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment