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Course: Physics library > Unit 18
Lesson 4: Discovery of batteries- Zinc copper cell (reduction-oxidation)
- How to measure?
- Battery meter (galvanometer)
- How Many Turns?
- Electrolyte test (pure water vs. vinegar)
- Reverse electrodes (polarity)
- Electrolyte (strong acid test)
- Electrolyte (salt test)
- Electrode (distance test)
- Electrolyte (temperature test)
- Electrode (surface area test)
- Standard cell
- How much electrolyte does a single cell need?
- The battery and electromagnetism
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How much electrolyte does a single cell need?
Observation: when we pull our cell out of the electrolyte it still causes a deflection, which increases when pressure is applied. How could this lead to more efficient batteries? Created by Brit Cruise.
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What is in between the coins?(7 votes)
I think it's a piece of sponge or thick card. Something that allows the solution to flow between it while keeping the two coins apart.(15 votes)
I think there is still some electrolyte left in between the coins(in the 'sponge'). Either that or once the electricity erodes the surface of the metals they continue reacting. I think the first explanation is correct. Am I right?(6 votes)
The spongy material between the two metals can replace the cup of saltwater because it has salt water absorbed within it! Therefor the cup of salt water is unnecessary except to re-wet the sponge!(2 votes)
is blood an electrolyte or a non electrolyte?(2 votes)
no blood itself is not an elecrolyte, but the minerals present in it are electrolytes(2 votes)
- Maybe off topic, but I don't know where to ask it. When we dissolve CuCl2 in water, the Chlorine takes Copper's electrons and becomes negatively charged. Copper becomes positively charged. When we insert an anode and a cathode, and connect the negative end of the power to the cathode, and apply potential difference, the copper ions move toward the cathode, accept electrons and get deposited there. This is electrolysis. The chlorine anions move towards the positive anode and lose their electrons, and this continues. A question. Chlorine is extremely electronegative, so why is it compelled to lose electrons? Also a normal Cl2 molecule dissolved wont conduct electricity, so why do ions? Thanks!(3 votes)
During the electrolysis of Aluminium Chloride, the carbon anode gets burned out, Why? Also give balanced equation for the process.(0 votes)
The deflection doesn't return to 0 because of the sponge in between the coins. It sucked in some of the salt water and caused the deflection to decrease, but not disappear. Am I right?(1 vote)
why cant they talk instead of subtitles?(1 vote)
What were the coins made up of? they might be working on thelogic that metals give electrons and with an electrolite they can for an ionic circuit causing current in the wires.(1 vote)
What would happen if they used lass wire?(1 vote)- the galvanometer would not be as sensitive.(1 vote)
do u have to use water to test the experiment ?(1 vote)
So one coin is still positively charged and the other negatively charged, so there's still some voltage between them? Giving a capacitance of sorts? I'm a little confused. If there is a voltage between them, that would give potential energy but what kind of potential energy is it? Since it's transforming into electromagnetic (or kinetic energy of the conventional current).(1 vote)
Video transcript
Deflection is zero. Deflection does not return to zero. Squeeze coins together. Deflection increases! Do we need the cup?