Which option correctly shows the concentration of h3o ions in pure water

In pure water, the concentration of \( \text{H}_3\text{O}^+ \) ions (hydronium ions) is \( 1.0 \times 10^{-7} \, \text{M} \) at 25 °C. This is due to the self-ionization of water, where water molecules dissociate into hydronium and hydroxide ions. Therefore, both the concentration of \( \text{H}_3\text{O}^+ \) and \( \text{OH}^- \) ions in pure water are equal, resulting in a neutral pH of 7.