Question

Which one of the following statements best describes the solution produced when an Arrhenius acid is dissolved in water? A) The only positive ion in solution is H . B) The only positive ion in solution is NH . C) The only negative ion in solution is OH . D) The only negative ion in solution is HCO .

Answer 1

Answer: Option (A) is the correct answer.

Explanation:

Arrhenius acids are the species which dissociate to give hydrogen ions, that is, $H^{+}$.

For example, $CH_{3}COOH + H_{2}O \rightleftharpoons H_{3}O^{+} + CH_{3}COO^{-}$

In the given example, HCN is donating the hydrogen ion therefore, it is an acid whereas $HPO^{2-}_{4}$ is accepting the hydrogen ions so it acts as a base.

Whereas according to Arrhenius, bases are the species which dissociate to give hydroxide ions, that is, $OH^{-}$.  

For example, $NaOH + H_{2}O \rightarrow Na^{+} + OH^{-}$

Thus, we can conclude that the statement only positive ion in solution is $H^{+}$ best describes the solution produced when an Arrhenius acid is dissolved in water.