Recent content by isaaclimdc

Yes, I agree with that, and that's why I have taken measurements for all three variables (R, I and V). However, I just need to know if P is expected to be constant or not? That is what is confusing me..

Okay... but let's say I plot a R vs I^2 graph, and its an exponential curve with negative gradient. Does the integral of the function from my lowest R value to the highest i took equal the power? It seems like power stays CONSTANT no matter what the resistance is! Since P=IV, and as R...

Yes, but why is it that the proportion between R and P are different in the two equations?

That is if P=I^2R right? But why is it that if P=V^2/R is used, you get a relationship that says otherwise?

Hi all, I'm doing a lab now to determine the relationship between the resistance of a resistor (colour-coded ones) and the energy and power dissipated. What kind of relationship is expected between the variables R and P, or R and E? The way I carried out the lab was to use different...

Is this the resistance and special resistance of the lead electrodes or the sulphuric acid? Also, how can I relate this to the distance between the electrodes? Sorry if I'm not comprehending...

Please help me!

Okay, I understand what you said about the Nernst Equation, but I think that does not link to the variables I'm testing. Well, I have two options: one is to look at the distance between the electrodes against the potential, and the other is to investigate the effects of sulfation on the cell...

Attached is my document for the Nernst equation.. I'm sorry I still don't get how all this applies! Just f.y.i, I'm doing this at high school IB level.. so I'm still quite inexperienced in this field. Are you also saying that I cannot have a chemical explanation as to why the IR increases...

I have tried the Nernst equation and it does not seem to work in this case, since the number of moles of electrons transferred is the same no matter the quantities. I don't really understand the ohmic drop: how does it depend on the sulfate ions in the electrolyte? Thanks for your help.

How does the amount of lead sulfate on the electrodes of a lead-acid battery affect its electric potential? The discharge reaction of a lead-acid battery produces amorphous lead (II) sulfate at the electrodes. If I can work out the number of moles of lead sulfate formed, how can I interpret...

Is there really no way else around this.. I really need this experiment to work..

Thanks for your replies. I understand what you're saying. However now, is there an alternative way for me to show the effects of sulphation in this manner, without the use of complex analytic methods? My teacher suggested the use of nitric acid. How does this work?

Does the design of my experiment sound feasible to you? It was all made up in my head without expert help, so I was wondering whether everything is valid?

Hi all, I'm doing this project entitled "determining the effects of Sulphation on lead-acid batteries", and what it essentially is, is the reason why these batteries lose their effectiveness after being left in a discharged state for a period of time. What happens is lead sulphate is formed...