What is the charge on iodine in the iodate ion (IO
3
−
)?
The Correct Answer and Explanation is :
The charge on iodine in the iodate ion, ( \text{IO}_3^- ), can be determined by analyzing the oxidation states of each element in the ion. In this ion, oxygen typically has an oxidation state of (-2). Since there are three oxygen atoms, their total contribution to the charge is ( 3 \times -2 = -6 ).
The overall charge on the iodate ion is (-1), which we’ll use to solve for the oxidation state of iodine (( x )):
[
x + (-6) = -1
]
Solving this equation:
[
x = -1 + 6 = +5
]
Thus, the oxidation state (or formal charge) of iodine in the iodate ion is ( +5 ).
Detailed Explanation
The iodate ion, ( \text{IO}_3^- ), is a polyatomic ion that consists of one iodine atom and three oxygen atoms. When analyzing ions like iodate, it’s helpful to consider the general rules for oxidation states:
- Oxygen: In most compounds, oxygen has an oxidation state of (-2), unless it’s in peroxides or bonded to fluorine. For ( \text{IO}_3^- ), oxygen retains its typical (-2) state.
- Iodine: The oxidation state of iodine is unknown initially, so we represent it as ( x ).
- Charge of the Ion: The total charge of ( \text{IO}_3^- ) is (-1).
The oxidation state of iodine in ( \text{IO}_3^- ) has significant chemical implications. For instance, iodine’s high positive oxidation state makes iodate a good oxidizing agent, often used in redox reactions. Understanding the oxidation states also helps in balancing reactions in acidic and basic environments, as well as predicting the behavior of iodate in various chemical reactions.
In summary, iodine in the iodate ion ( \text{IO}_3^- ) carries an oxidation state of ( +5 ), balancing the three (-2) charges from oxygen to result in the ion’s overall (-1) charge. This concept of oxidation states is critical in chemistry for understanding electron distribution and predicting reactivity.