Hi, I have been trying to solve the Equilibrium Constant for my lab work. Some of the solutions have reactants with an equilibrium concentration of 0 M. Does this mean my Equilibrium Constant will be undefined since the denominator becomes zero when I use the formula for Equilibrium Constant?

Thanks

 

Edited July 30, 20214 yr by Retinu
Wrong image attached

Hopefully your wet chemistry is better than your maths.

(No offence meant)

 

Those two ions can't be the only reactants.

Can you say why not ?

The equilibrium constant is defined in terms of all reactants and products.

But some reactions are multistep, which means that there will be intermediate reations where the products of one reaction form the reactions of the next.
 

You should always start with the stoichiometric reaction and work from there ?

 

This publication may help you

https://pubs.acs.org/doi/10.1021/ja01545a015

Edited July 30, 20214 yr by studiot

Hi, this is a very new topic to me, and I just followed the steps that our professor taught us through a 9 minute video. Based on my professor's video, this is the final step of the whole thing, and I now need to solve for the equilibrium constant using the formula K = [products]/[reactants]. I am genuinely very confused at this point because even the top students in my class are getting the same results that I got.

Edit: I finally figured it out below.

50 minutes ago, studiot said:

Hopefully your wet chemistry is better than your maths.

(No offence meant)

 

Those two ions can't be the only reactants.

Can you say why not ?

The equilibrium constant is defined in terms of all reactants and products.

But some reactions are multistep, which means that there will be intermediate reations where the products of one reaction form the reactions of the next.
 

You should always start with the stoichiometric reaction and work from there ?

 

This publication may help you

https://pubs.acs.org/doi/10.1021/ja01545a015

I think I finally figured it out. I just followed what my primary chemistry professor taught us since this was taught to us by a substitute. Thank you so much for pointing out that it was incorrect, if not, I wouldn't have tried answering it again. My equilibrium constants looks normal now :))

Edited July 30, 20214 yr by Retinu
Clarity

I have atteched some information about  ferric thiocyanate that may be useful.

Here also is another paper on the kinetics you are asking about.

https://web.williams.edu/wp-etc/chemistry/epeacock/EPL_CHEM_361/CHEM361_LAB_DIR/JACS80.2961.58.pdf

I cannot be more specific without more information.

Also you have not answered my questions.

For your information here is the advice given to Pharmacy students at Robert Gordon University.

Labs.

Make sure you understand what your experiment is about and what you are trying to achieve, before you arrive at the laboratory.

Make sure you show your results to the experiment supervisor and discuss them before you leave the lab.

In the first year we provide a workbook to record your results and describe the experiments.

 

Experience shows that, particularly in the first year, many students leave with nil or incomplete or otherwise unsatisfactory results.
The workbook is designed to help overcome this.

Edited July 30, 20214 yr by studiot