When an electric cell is connected to a circuit, electrons flow away from the negative terminal in the circuit. But within the cell, electrons flow to the negative terminal. Explain.

Solution

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Let's take the simple electric cell, as you see in the figure below.

The chemical reaction inside the cell (battery) dissolves the zinc atoms from the zinc electrode which means that the zinc atom enters the solution (sulfuric acid) as a positive ion and it leaves two electrons behind on the zinc electrode.

Now the zinc electrode is negative and the solution itself is positive. So the solution attracts electrons from the carbon electrode.

This means that the carbon electrode is becoming positively charged since it loses the electrons.

When the circuit is open, as the first figure below, this process stops after a short time because the zinc dissolving process stops.

This happens because the zinc electrode will be increasingly negative, any new positive zinc ions produced are attracted back to the electrode. But when the circuit is closed, as the second figure below, this process continues and more zinc atom dissolves. The electrons leave the zinc electrode to the lightbulb and continue in the wire to the carbon electrode. And the carbon electrode loses them into the solution, and so on.