Tuesday, April 08, 2008

The Chemistry Student's Nemesis

We got this catalogue in the mail today and it made me think of stiochiometry.

Moles are actually killed using the unusual poison zinc phosphide. It seems the poison is an effective rodenticide and the rodents find the chemical attractive. The label claims they will die in their tunnels within a day of ingesting the poison.

The reaction to produce zinc phosphide from the elements makes for an interesting balanced chemical equation. I will give an appropriately geeky / nerdy prize to the first ABU student that gives me a correct balanced chemical equation in the comment section of this post and tells me what mass of mole killer they could make from 40 grams of phosphorus.

6 comments:

cwj said...

Balanced Equation:
6Zn(s) + P4(s) -> 2Zn3P2(s)

40.0g P4 * (1 mol P4/123.895 g P4)
= 0.323 mol P4

0.323 mol P4 * (2 mol Zn3P2/1 mol P4)
= 0.646 mol Zn3P2

0.646 mol Zn3P2 * (258.118g Zn3P2/1 mol Zn3P2)
= 166.74g Zn3P2

40 g of P4 would produce 166.74g of Zn3P2 (mole killer) assuming there was enough Zinc available for all the phosphorus to react.

AND assuming I got the equation right. If not, well... it is all wrong.

Thanks Honeydew. That was exactly what I needed to do one week before classes end with all the work I still have to accomplish.

:P

cwj

Professor Honeydew said...

Well there you have it. Well done. Next time we cross paths we will sort out a sufficiently nerdy prize. I honestly didn't think anyone was reading this thing ... I guess now I don't know if anyone else but you is reading this blog. Thanks, once again you made my day.

Anonymous said...

For the record, I read the blogs too.

Professor Honeydew said...

Really? I would have thought that your stress level was too high and your tolerance for frivolity to low at this stage of your honours project for anything but goth or emo blogs.

Anonymous said...

I read them. At this point, however, I don't bother trying to figure out questions of any sort unless they directly relate to the outcome of this semester. I leave that up to Chris :), because apparently he has more time than I do. (What Psalm are you on, Christopher...?) :P

Professor Honeydew said...

O! O! Everybody! Catfight right here on Prof. H's comment section. CWJ I do believe that you have been both dissed and called out. I'll put a quarter down on J. (she may be small but I suspect she fights dirty).