What is true of a basic solution at room temperature? it has a ph value below 7. it has a higher concentration of hydroxide ions than hydronium ions. it has a distinct sour taste but no odor. it releases hydrogen ions in a reaction.

It has a higher concentration of hydroxide ions than hydronium ions.

Explanation:

A basic solution has pH value above 7, neutral solutions have pH equal to 7, and acid solutions pH value below 7.

The value of pH is , where is the concentration of ion hydronium. As higher is its value, low will be pH. When water dissociates, besides hydronium, it forms hydroxide , so, for a basic solution, the concentration of hydroxide will be higher than the concentration of hydronium.

Some bases have a sour taste, some of them have an odor. So it's not possible to identify the solution by that.

As explained above, basic solutions release hydroxide ions in a reaction. Acids solutions release hydrogen ions or hydronium anions.