Which type of reactions should be avoided for determining oxidation potential values?

Determining oxidation potential values requires careful consideration of the reactants and products involved in the reactions. Reactions with ions in the reactants are generally more complex when it comes to measuring oxidation potentials, primarily because the presence of ions can alter the solution's activity and introduce complications related to the calculation of standard potentials.

In electrochemistry, the standard electrode potential is typically measured under ideal conditions. Reactions with ions at the start can often lead to deviations from these ideal conditions due to interactions in solution. Furthermore, the existence of ions can impact the electronegativity and the potential energy of the reaction, complicating the assignments of oxidation states and thus the potential values.

Conversely, reactions involving metals in the products or gases may offer more straightforward measurement conditions. Reactions that release heat can also be managed within calorimetric contexts while still providing useful information about oxidation states. Thus, focusing on reactions with ions in the reactants is generally not ideal for assessing oxidation potential, making this choice a key consideration in such evaluations.