Electrolysis of aqueous HCl produces:

The electrolysis of aqueous HCl (hydrochloric acid) produces hydrogen gas (H2) and chlorine gas (Cl2). This process occurs at the electrodes when an electric current is passed through the solution, leading to the following reactions at the electrodes:

At the cathode (negative electrode):
2H⁺(aq) + 2e⁻ → H2(g)

Hydrogen ions (H⁺) from the hydrochloric acid gain electrons (2e⁻) at the cathode to form hydrogen gas (H2).

At the anode (positive electrode):
2Cl⁻(aq) → Cl2(g) + 2e⁻

Chloride ions (Cl⁻) from the hydrochloric acid lose electrons (2e⁻) at the anode to form chlorine gas (Cl2).

So, the overall reaction for the electrolysis of aqueous HCl is:

2HCl(aq) → H2(g) + Cl2(g)

This process is used industrially to produce hydrogen and chlorine gas, which have various applications.