1. Protons:
* Hydrogen (H): Each hydrogen atom has 1 proton.
* Oxygen (O): Oxygen has 8 protons.
* Total: 1 (H) + 1 (H) + 1 (H) + 8 (O) = 11 protons
2. Electrons:
* Neutral atoms: Atoms have an equal number of protons and electrons.
* Hydronium ion (H₃O⁺): The positive charge indicates that the ion has lost one electron.
* Total: 11 (protons) - 1 (lost electron) = 10 electrons
Therefore, H₃O⁺ has 11 protons and 10 electrons.
