Final answer:
To draw the Lewis structure for the hydronium (H₃O) cation, identify the central atom as hydrogen, add the extra electron for the single negative charge, and distribute electrons to form an octet. The structure is represented as [H₃O]+.
Step-by-step explanation:
To draw the Lewis structure for the hydronium (H₃O) cation, follow these steps:
- Identify the central atom, which in this case is hydrogen (H).
- Add the extra electron to the central atom to account for the single negative charge of the polyatomic ion.
- Pair the electrons and draw the central atom bonded to two other hydrogen atoms.
- Distribute the remaining six electrons around the oxygen (O) to form an octet.
- Enclose the entire polyatomic ion in brackets with the charge, +1, as a superscript outside the brackets.
The Lewis structure for the hydronium cation is represented as [H₃O]+.