Which of the following is the correct chemical formula for the hydronium ion?

• A. OH^-
• B. H3O^+
• C. NH4^+
• D. HCO3^-

Answer: (B)

Verified step by step guidance

1. Understand that the hydronium ion is formed when a water molecule (H2O) gains an extra proton (H+).
2. Recognize that adding a proton (H+) to H2O results in H3O+, which carries a positive charge.
3. Recall the chemical formula for the hydroxide ion is OH-, which is different from hydronium.
4. Note that NH4+ is the ammonium ion, and HCO3- is the bicarbonate ion, both distinct from hydronium.
5. Conclude that the correct chemical formula for the hydronium ion is \(H3O^{+}\).