Final answer:
Chlorine gas is released at the positive anode during the electrolysis of aqueous NaCl solution, as chloride ions are oxidized. Hydrogen gas is released at the negative electrode due to the reduction of water molecules.
Step-by-step explanation:
During the electrolysis of aqueous NaCl solution using inert electrodes, the reaction that occurs at the anode, which is the positive electrode, is the oxidation of chloride ions (Cl-) to form chlorine gas (Cl2). This can be represented by the half-equation:
2Cl-(aq) → Cl2(g) + 2e-
Thus, chlorine is released at the positive anode. At the negative anode, hydrogen gas is released as a result of the reduction of water molecules, not sodium ions, because of their more favorable reduction potential.