An electrolysis experiment is halted, and the connections to the...

During electrolysis, a back EMF $e$ is developed in the cell due to the accumulation of products at the electrodes, which opposes the applied EMF $E$.

The effective EMF in the circuit is $E - e$, and the initial current is $I_1 = \dfrac{E - e}{R}$, where $R$ is the resistance of the circuit.

When the battery terminals are reversed, the applied EMF $E$ and the back EMF $e$ act in the same direction. The new effective EMF becomes $E + e$.

The new current in the circuit is $I_2 = \dfrac{E + e}{R}$.

Since $I_2 > I_1$, the magnitude of the current in the circuit increases.

The rate of heat generation is given by $I^2 R$. As the current increases, heat will be generated at an increased rate.

According to Faraday's first law of electrolysis, the rate of material liberation is $\dfrac{dm}{dt} = ZI$. Since the current increases, the rate at which material is liberated at the electrodes will also increase.