To determine the oxidation state of chromium and the chemical formula of chromium(III) sulfate, follow these steps:
1. Understanding the given information:
- Chromium(III) indicates that the oxidation state of chromium is +3.
- Sulfate is a polyatomic ion with the formula [tex]\( \text{SO}_4^{2-} \)[/tex].
2. Oxidation State of Chromium:
- The term "Chromium(III)" tells us that the oxidation state of chromium is +3. This is because the Roman numeral III suggests an oxidation state of +3.
3. Neutral Compound Formation:
- In order to form a neutral compound, the total positive charge must balance the total negative charge.
- Chromium has an oxidation state of +3, so each chromium ion contributes a +3 charge.
- Sulfate ([tex]\( \text{SO}_4^{2-} \)[/tex]) has a charge of -2.
4. Balancing the Charges:
- To balance the charges between chromium and sulfate:
- Two chromium ions (each +3) give a total charge of [tex]\( 2 \times (+3) = +6 \)[/tex].
- Three sulfate ions (each -2) give a total charge of [tex]\( 3 \times (-2) = -6 \)[/tex].
5. Writing the Chemical Formula:
- The formula needs to represent a neutral compound. Since the charges are balanced with two chromium ions and three sulfate ions, the chemical formula will be [tex]\( \text{Cr}_2(\text{SO}_4)_3 \)[/tex].
Therefore, the oxidation state of chromium in this compound is [tex]\( \boxed{3} \)[/tex], and the chemical formula of the compound is [tex]\( \boxed{\text{Cr}_2(\text{SO}_4)_3} \)[/tex].
