In the electrolysis of molten \(\mathrm{BaI}_{2}\) (a) What product forms at the negative electrode? (b) What product forms at the positive electrode?

During the electrolysis of molten \(\text{BaI}_2\), the ions move towards their respective electrodes based on their charge. The system has a negative electrode (cathode) and a positive electrode (anode). The nature of the reactions occurring at these electrodes depends on the movement of ions.

At the cathode, reduction takes place. Reduction is the gain of electrons. In this process, \(\text{Ba}^{2+}\) ions migrate to the cathode where they gain electrons to form barium metal (\(\text{Ba (s)}\)).

At the anode, oxidation occurs. Oxidation is the loss of electrons. Here, \(\text{I}^{-}\) ions move towards the anode where they lose electrons to form iodine gas (\(\text{I}_2 (g)\)).

This movement of ions ensures that each ion goes to the appropriate electrode to undergo the correct electrochemical reaction.

The principles of oxidation and reduction are essential in understanding electrolysis.

Oxidation: This involves the loss of electrons. During the electrolysis of molten \(\text{BaI}_2\), \(\text{I}^{-}\) ions at the anode (positive electrode) lose electrons to form iodine gas.
The reaction at the anode is:
\[2\text{I}^{-} \rightarrow \text{I}_2 (g) + 2e^{-}\]

Reduction: This is the gain of electrons. In the same scenario, \(\text{Ba}^{2+}\) ions at the cathode (negative electrode) gain electrons to form solid barium.
The reaction at the cathode is:
\[\text{Ba}^{2+} + 2e^{-} \rightarrow \text{Ba (s)}\]

In simple terms, oxidation always involves losing electrons and reduction always involves gaining electrons. The mnemonic 'OIL RIG' can help you remember: Oxidation Is Loss, Reduction Is Gain.

In electrolysis, the movement of ions is key to the reaction occurring.

When molten \(\text{BaI}_2\) is subjected to electrolysis, it dissociates into \(\text{Ba}^{2+}\) and \(\text{I}^{-}\) ions.

• Positive ions (cations) like \(\text{Ba}^{2+}\) move towards the negative electrode (cathode).
• Negative ions (anions) like \(\text{I}^{-}\) move towards the positive electrode (anode).

This directional movement is driven by the attraction between opposite charges.

At the cathode, the positive \(\text{Ba}^{2+}\) ions gain electrons (reduction) to form barium metal. At the anode, the negative \(\text{I}^{-}\) ions lose electrons (oxidation) to form iodine gas.

By understanding this movement and the resulting electrode reactions, one can predict the products of electrolysis effectively.