Final answer:
Reactions in solutions involving ions are significant mainly because they often result in redox reactions. These processes generally occur in aqueous solutions and are subject to temperature variation, which can affect their rate.
Step-by-step explanation:
Reactions in solutions involving ions are significant because they often involve redox reactions, where there is a transfer of electrons between species. These reactions frequently occur in water, known as aqueous solutions, and can be categorized into precipitation reactions, acid-base reactions, and redox reactions.
Reactions in aqueous solutions are influenced by a variety of factors, including temperature. Nearly all chemical reactions occur at a faster rate at higher temperatures, because increased kinetic energy leads to more frequent contact between reactants. Therefore, these reactions are not insensitive to temperature changes, contrary to one of the options provided in the question.
Furthermore, the rate of these reactions can vary; they do not universally follow zero-order kinetics and can occur faster than gas-phase reactions, depending on the reactive elements and conditions involved.