I know that the salt bridge produces ions to balance out the positive and negative ions in each solution, but why won't it work without a salt bride? Would it even work at the start since there's few electrons gained and lost and few ions produced?
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It would work vanishingly briefly. The separation of charge that occurs when you connect two separated half cells without a salt bridge produces an electrostatic potential difference that opposes the electrochemical potential difference. The cell reaction would proceed until the two voltages balance, and it doesn't take much charge separation to hit the 1–2 volt electrochemical potential of typical cells, so this process is very fast.
answered Oct 21, 2014 at 17:33
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$\begingroup$ Would it be correct to say this is like shorting a battery $\endgroup$– BrianCommented Jun 7, 2021 at 2:00
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1$\begingroup$ @Buraian The effect is actually the complete opposite; more like sawing a battery in half and trying to connect a circuit to the two halves. When you short a battery, both half cells will proceed to react as fast as they can until they are limited by something else, e.g., mass transport. $\endgroup$ Commented Jun 7, 2021 at 17:16
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$\begingroup$ @MichaelDMDryden It wouldn't occur "vanishingly briefly" -- after all, these things can last a while! $\endgroup$– ManRowCommented Jan 25, 2023 at 12:19
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$\begingroup$ @ManRow If you look at the last paragraph in Theory: "For this protection to work there must be an electron pathway between the anode and the metal to be protected (e.g., a wire or direct contact) and an ion pathway between both the oxidizing agent (e.g., oxygen and water or moist soil) and the anode, and the oxidizing agent and the metal to be protected, thus forming a closed circuit; therefore simply bolting a piece of active metal such as zinc to a less active metal, such as mild steel, in air (a poor ionic conductor) will not furnish any protection. " $\endgroup$ Commented Jan 25, 2023 at 21:41
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$\begingroup$ @MichaelDMDryden and what does that have to do with my comment?? Did you see me use the word "air" anywhere at all? I was replying to your answer and refuting your claim that a "no-salt-bridge" aka single cell galvanic current would last only "vanishingly briefly". I even gave you an example too -- the sacrificial anodes, like the kinds used on ship hulls, clearly do not function merely only "vanishingly briefly"! (nor do ships often complete their trips "vanishingly briefly" for that matter either) $\endgroup$– ManRowCommented Jan 26, 2023 at 3:46