The Student Room Group
Reply 1
H2SO4 is a strong acid and therefore will have almost entirely dissociated into its ions H+ and SO42-. Therefore a greater current can pass through H2SO4 than through water and thus electroylsis will occur quicker.
Reply 2
To put it using more technical terms: solution of sulfuric acid has much lower resistance, thus much higher current can flow. Pure water is a pretty good insulator.

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