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Zinc copper cell (reduction-oxidation)

Zinc Copper cell - example of reduction-oxidation reaction. Created by Brit Cruise.

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  • leafers ultimate style avatar for user eightsquare
    CH3COOH is the main constituent of vinegar. Zinc oxide is amphoteric, so I'm assuming that zinc is more electronegative than copper and accepts electrons during the reaction. CH3COOH being acidic must be an oxidising agent. Therefore when the current is on, CH3COOH breaks down into two ions, CH3CO+ and OH-, and copper is oxidised, hence explaining the bubbles on copper. Am I right? I can't explain the bubbles on zinc before the current is turned on...
    (10 votes)
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    • leaf green style avatar for user hrisikesh27
      Actually, when a metal reacts with an acid, a salt and hydrogen gas is produced.So when Zinc [ being a metal] reacts with ethanoic acid [ main constituent of vinegar], a salt Zinc ethanoate is produced along with hydrogen gas. We see the bubbles only because of the formation of hydrogen gas.
      (12 votes)
  • leaf green style avatar for user Dane Sheridan
    This blew my mind. What did happen?
    (4 votes)
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    • mr pants teal style avatar for user Simeon Nichols
      Here's what I think happened: upon adding the Zinc to the vinegar (or acetic acid CH3COOH) it reacts to form hydrogen gas (the bubbles) in the reaction Zn(s) + 2CH3COOH(aq) = Zn(CH3COO)2(aq) +H2(g); during this reaction the Zinc is Oxidised (it looses electrons) and becomes positively charged: *Zn = Zn^2+ + 2e-*. This is where I'm having trouble; I think the copper doesn't produce bubbles as it needs an oxidising agent present or the reaction is very slow because copper has what's known as a positive reduction potential which just means that it is more likely to be reduced (gain electrons) than oxidised (lose electrons). When the wires are connected the electrons released from the Zinc produce a current and move to the copper; this gives the H+ ions in the acidic solution a chance to combine and form H2(g) which is released as bubbles.
      (3 votes)
  • aqualine ultimate style avatar for user yasser
    what job does vinegar do there??
    (3 votes)
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  • male robot donald style avatar for user Function 97
    Why was he using vinegar? Would water work?
    (3 votes)
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  • piceratops ultimate style avatar for user Jack Owen
    How come when the two wires connect the copper does not erode?
    (3 votes)
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  • starky ultimate style avatar for user UMARBFD786
    wouldn't he get an electric shock
    (1 vote)
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  • old spice man green style avatar for user CielAllen08
    where can you get those wires that he has if you want to do the experiment yourself?
    (1 vote)
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  • piceratops ultimate style avatar for user Carmel01
    If you put a light bulb on the end with the copper wire instead of the wire would the light bulb light up?
    (1 vote)
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  • mr pants teal style avatar for user Abigail Abigail
    What is zinc?
    (2 votes)
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  • mr pants teal style avatar for user Abigail Abigail
    What is zinc?!
    (2 votes)
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Video transcript

ocet miedziany drut cynkowy gwóźdź bąbelki na cynku brak bąbelków na miedzi połącz druty bąbelki tworzą się na miedzi