How do you predict products of electrolysis in aqueous solutions?

To predict products of electrolysis in aqueous solutions, consider the reactivity series and the ions present in the solution.

Electrolysis is a process where electrical energy is used to drive a non-spontaneous chemical reaction. In an aqueous solution, electrolysis can produce a variety of products depending on the ions present in the solution and their position in the reactivity series.

Firstly, you need to identify the ions present in the solution. These could be positive ions (cations) or negative ions (anions). The cations are usually metal ions or hydrogen ions, while the anions are often hydroxide ions or non-metal ions.

Next, consider the reactivity series. This is a list of elements ordered by their reactivity, with the most reactive at the top. During electrolysis, the least reactive cation and the least reactive anion are usually discharged at the electrodes. For example, if the cations are a metal ion and hydrogen, and the metal is less reactive than hydrogen (like copper), the metal will be discharged at the cathode. If the anions are hydroxide and a non-metal ion, the hydroxide ions are usually discharged at the anode, producing oxygen gas.

However, if the solution is highly concentrated with a non-metal ion (like chloride ions in a concentrated solution of sodium chloride), then the non-metal ion may be discharged at the anode instead of the hydroxide ion. This would produce chlorine gas.

Remember, the specific conditions of the electrolysis, such as the concentration of the solution and the type of electrodes used, can also influence which ions are discharged. Therefore, predicting the products of electrolysis requires a good understanding of the reactivity series, the ions present in the solution, and the conditions of the electrolysis.