Answer:
e. all the answers above are correct.
Step-by-step explanation:
A hydronium ion:
a. has the structure H₃O⁺. YES, this is the chemical formula of the hydronium ion.
b. is a hydrated hydrogen ion. YES, it is formed according to the equation:
H⁺ + H₂O ⇒ H₃O⁺
c. is a hydrated proton. YES, since proton is the name given to the hydrogen ion
d. is the usual form of one of the dissociation products of water in solution. YES, according to the following equation:
2 H₂O ⇒ H₃O⁺ + OH⁻