## Chemistry (4th Edition)

- No, we can't conclude that a solution with pH = 6.7 is acidic. - We need to know the temperature of the solution. - Yes, the pH can be 0 or negative. - A solution with $1.0M$ of $[H_3O^+]$ has pH = 0. - A solution with $10.0M$ of $[H_3O^+]$ has pH = -1.
The temperature can change the equilibrium of the reaction: $2H_2O(l) \lt -- \gt H_3O^+(aq) + OH^-(aq)$ - Therefore, it can change the $K_w$, where the acidity and basicity is based on. - $-log(1.0) = 0$ - $-log(10.0) = -1$