- A polyatomic ion is a charged species containing two or more covalently bonded atoms.
- \(H_2\) is a neutral molecule.
- \(Mg^{+}\) and \(Ne^{+-}\) are monatomic species.
- \(CO_3^{-}\) consists of multiple atoms and carries a charge, making it a polyatomic ion.
- The final answer is \(\boxed{CO_3^{-}}\).
Explanation
- Analysis of the options
A polyatomic ion is defined as a chemical species consisting of two or more atoms covalently bonded together that carries a net electrical charge. To determine which option is a polyatomic ion, we evaluate the provided choices:
- \(H_2\): This is a diatomic molecule composed of two hydrogen atoms. Because it has no net electrical charge, it is not an ion.
- \(CO_3^{-}\): This species is composed of a carbon atom and three oxygen atoms covalently bonded together. Since it carries a net charge of -1 (it is an ion containing multiple atoms), it fits the definition of a polyatomic ion.
- \(Mg^{+}\): This is a monatomic ion, consisting of a single magnesium atom with a positive charge. Since it does not contain multiple atoms, it is not polyatomic.
- \(Ne^{+-}\): This notation represents a single neon atom. It does not consist of multiple atoms and is not a stable ion configuration, therefore it is not a polyatomic ion.
- Conclusion
Based on the definition provided in the first step, we compare each option to the criteria of being composed of multiple atoms and carrying a net electrical charge:
- \(H_2\) is a molecule, not an ion.
- \(CO_3^{-}\) is composed of multiple atoms (carbon and oxygen) and carries a net charge.
- \(Mg^{+}\) is a monatomic ion.
- \(Ne^{+-}\) is a monatomic species with invalid notation.
Thus, the only correct example of a polyatomic ion from the given list is \(CO_3^{-}\).
Examples
In the study of chemistry, polyatomic ions are fundamental building blocks for many compounds we encounter daily. For example, the bicarbonate ion (\(HCO_3^-\)) is a polyatomic ion that plays a crucial role in buffering the pH level of human blood, ensuring it remains within a safe range. Understanding how atoms bond covalently and how they form charged groups allows chemists to predict the properties and reactions of these essential substances, such as those used in antacids or baking soda.