The electrical energy produced from chemical reactions

AI Thread Summary
Different metal combinations in electrochemical cells, such as lemon batteries, produce varying voltages and currents, affecting power output. The total energy output is influenced by the quantity of active materials, such as the size of metal sheets and the amount of acid used. While different metals yield different voltages, the overall energy produced can vary based on these factors. The discussion highlights the relationship between metal reactivity and energy generation in chemical reactions. Understanding these principles is essential for optimizing energy output in electrochemical systems.
longchair
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Hi there, new member here
(**TL,DR is available at the bottom of this post**)

As you may or may not know, if you were to put in a plate of zinc at one end and a plate of copper at the other, put them in an acid solution, electricity will be produced.
More of that stuff here: https://en.wikipedia.org/wiki/Lemon_battery

However, it doesn't necessarily have to be copper and zinc. You could use different metals (with different reactivity) including aluminum, lead, silver, etc;

After some experimentation, I found out that different combinations of metals produced different voltages and current, thus different power output as well.

But, do these different combinations of metals produce different amounts of total energy? Or is it that the total energy produce will be the same, and a lower power output results in the system lasting longer.

TL,DR
In the lemon battery (and most other metals), we can use different metals (with different re-activity) to generate electricity. Do all combinations result in the same total output of energy?

Thank you very much for your time
Any response will be appreciated
 
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"After some experimentation, I found out that different combinations of metals produced different voltages and current, thus different power output as well."

Congratulations! You have re-discovered the electro-chemical series for metals.
 
Ok, sorry I guess I worded that wrong. It is obvious that this is true, so I apologize for that. I just wanted to point out that this indeed true, and that I have done some validation.
But does the total energy output differ anyways?
Thanks
 
Hi longchair,

The voltage is dependent upon the chemistries in the cell. The energy available is dependent on the quantities of the active constituents. A cell made with larger sheets of metal and more acid can deliver more energy.
 
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