$$ \ce{2H2O <--> H3O+(aq) + OH-(aq)} $$

The autoionization of water is represented by the equation above. Values of p\(K_w\) at various temperatures are listed in the table below.

$$ \begin{array}{|c|c|} \hline \text{Temperature} (^\circ \text{C}) & \text{p}K_w \\ \hline \hline 0 & 14.9 \\ \hline 10 & 14.5 \\ \hline 20 & 14.2 \\ \hline 30 & 13.8 \\ \hline 40 & 13.5 \\ \hline \end{array} $$

Based on the information above, which of the following statements is true?

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We can use the equation:

$$ \text{pH} + \text{pOH} = \text{p}K_w $$

As the temperature increases, p\(K_w\) decreases. If p\(K_w\) decreases, pH and pOH also decrease.

Generally, as temperature increases, ions will dissociate easier. Since there are more hydroxide and hydronium ions in water, the pH and pOH will decrease.