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Physics library
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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Electrolyte (salt test)
What happens to the deflection when we add salt to an electrolyte? Why? Created by Brit Cruise.
Want to join the conversation?
- Say he put, oh, a quarter cup of salt in. If he put put a half a cup of salt in, the needle would spin a ways farther?(11 votes)
- more salt = more ions so yes, but only until the solution reaches saturation. To add more beyond that point won't change the needle because the salt doesn't dissolve (unless the solution is heated).(13 votes)
- I keep noticing French on the bottles that Brit uses. Is he from Canada?(2 votes)
- You called it! "In" Canada at least. "From" Canada unclear but very very likely. We might note that Canada isn't the only place where this phenomena is observed :)(4 votes)
- Please give examples of electrolytic cell and non-electrolytic cell.....(2 votes)
- Will this work in sea water or (the ocean)?(1 vote)
- Hello Hidalgotj,
Yes, it will work in sea water. The real question is will you be able to detect it with this crude compass measurement device.
This sounds like a good science experiment. If you had a good voltmeter you could see how the voltage changes as a function of the salt concentration.
On a related note you may be interested in the string galvanometer:
http://www.hektoeninternational.org/index.php?option=com_content&view=article&id=16
Regards,
APD(2 votes)
- Atwhat does the salt contain that makes the compass arrow move? Is it some magnetic properties? 0:47(1 vote)
- The salt contains positively and negatively charged ions. The two kinds create a sort of path for electricity through the water, giving it more current. More current is more magnetism.(1 vote)
- Would a salt that contains a bivalent kation like magnesium or calcium be an even better electrical conductor than the monovalent sodium?(1 vote)
- Will it still work if there wasn't any water in the cup, only salt?(1 vote)
- If salt water is an electric conductor then why doesn't it short-circuit the whole thing and lead the current straight through the water?(1 vote)
- because he shows you hands on than then not showing just talking(1 vote)
- what does the salt do so the compass could move ?(1 vote)
Video transcript
su xörək duzu elektrod 1 :duzsuz , elektrod 2: duzlu