Which of the following is NOT a characteristic of inorganic acids?

The correct answer identifies that inorganic acids do not have hydroxide as their main constituent. Inorganic acids, such as hydrochloric acid (HCl) or sulfuric acid (H2SO4), are primarily composed of hydrogen ions (H+) and an anion, which gives them their acidic properties.

The characteristic of tasting sour is typical of acids due to their nature; this is a well-known property of acids in general, including inorganic acids. Additionally, inorganic acids have the ability to conduct electricity because they dissociate into ions when dissolved in water. The presence of these ions allows the solution to conduct an electric current. Lastly, the ability of inorganic acids to turn blue litmus paper red is another defining characteristic of acids, as they release hydrogen ions that increase the concentration of H+ in an aqueous solution, thus lowering the pH and indicating acidity.

In summary, the main reason that the chosen option is correct is that hydroxide is associated with bases rather than acids. Therefore, it contradicts the fundamental composition that defines inorganic acids.