Question

which statement about the self-ionization of water is correct?
○ two water molecules interact to form a water molecule and a hydroxide ion.
○ two water molecules interact to form a hydronium ion and a hydroxide ion.
○ two water molecules interact to form two hydronium ions.
○ two water molecules interact to form two hydroxide ions.

Explanation:

The self - ionization of water is represented by the equation $\ce{2H_2O
ightleftharpoons H_3O^+ + OH^-}$. In this reaction, one water molecule donates a proton ($\ce{H^+}$) to another water molecule. The water molecule that accepts the proton forms a hydronium ion ($\ce{H_3O^+}$), and the water molecule that donates the proton forms a hydroxide ion ($\ce{OH^-}$). So two water molecules interact to form a hydronium ion and a hydroxide ion. The first option is incorrect as it does not form the correct ions. The third option is incorrect because two water molecules do not form two hydronium ions. The fourth option is incorrect as two water molecules do not form two hydroxide ions.

Answer:

B. Two water molecules interact to form a hydronium ion and a hydroxide ion.