Question

question 37 (1 point)
which of these is present in all acid-base systems?
○ hydronium ions
○ hydroxide ions
○ oxygen ions
○ a and b
○ a, b, and c

Explanation:

In acid - base systems, according to the Brønsted - Lowry theory, an acid donates a proton ($\ce{H+}$) and a base accepts a proton. When a proton is donated in an aqueous solution, it combines with a water molecule to form hydronium ions ($\ce{H3O+}$). For a base, when it accepts a proton, in many cases (especially in aqueous solutions related to Arrhenius theory, but also in broader Brønsted - Lowry contexts where water can be involved), hydroxide ions ($\ce{OH-}$) can be formed or are related to the base's action. Oxygen ions are not a part of all acid - base systems (many acids and bases don't involve oxygen ions directly). So hydronium ions (from acid - proton donation and combination with water) and hydroxide ions (from base - proton acceptance and related reactions, especially in aqueous media which is a common acid - base environment) are present in all acid - base systems.

Answer:

D. a and b (where a is hydronium ions and b is hydroxide ions)