catalyst

[NwJosh]

We've done an experiment on the rate of reactions using catalysts, we now have to do a right up of it and I'm stuck on explaining how the catalysts worked in the experiment i know that the help break chemical bonds in reactant molecules and provide a 'different pathway' for the reaction, but how do they do it.

 

The experiment was using 10cm3 potassium iodide solution, 10cm3 sodium thiosulfate solution, 5cm3 starch solution add the catalysts and then add 20cm3 of potassium peroxodisulfate solution

I've been told by my teacher that it is something to do with the shape of the molecule and the catalysts, but i cant remember exactly what she said, or that i understood it.

 

Edited February 15, 2011 by NwJosh

[Horza2002]

First of all, you need to work out what reaction has occured; right out the chemical equation.

 

Once you have that, it might help to come up with the mechanism for this reaction (or at least what is turning tinto what).

 

Your right in that a catalysts provides the reaction with an alternative route to the product (and product to reagents; remember catalysts don't alter the position of equilibrium, just the rate at which you get there) which is lower in energy somehow.

 

Once you have an idea how the reaction occurs without the catalyst, look at the structure of the catalyst and then think how it might help the reaction. If your teacher told you it had to do with shape, then I would believe him/her.

[vargo100]

If you say this

gd (¬Î`(d héJ8° eˆ„ üƒÜ

3à4;€.ÖŽ÷îbad°

ÆÞ- Z*õòO&Íúû3©ã–·ß‡ºJTÊ+Öð͆­¢ÞŒ£¾]òì˜o ÛŒ*J J†9Ýöö¬—_0¾­Áå\Ko?£—(Ùy9Þ‹]šUŸãÆ1ü?,#•äUÈ ÐÇfçx>wd­e¤P

[mississippichem]

If you say this

gd (¬Î`(d héJ8° eˆ„ üƒÜ

3à4;€.ÖŽ÷îbad°

ÆÞ- Z*õòO&Íúû3©ã–·ß‡ºJTÊ+Öð͆­¢ÞŒ£¾]òì˜o ÛŒ*J J†9Ýöö¬—_0¾­Áå\Ko?£—(Ùy9Þ‹]šUŸãÆ1ü?,#•äUÈ ÐÇfçx>wd­e¤P

 

Your equation isn't rendering on my browser. Try again with [ce] or [math] tags.