IUPAC name of complex ion `[CrCl_(2)(Ox)_(2)]^(3-)` is

Options

A. dichlorodioxalatochromium (III)
B. dioxaladichlorochromate (III)
C. dichlorodioxalatochromate (III)
D. bisoxlaedichlorochromate (III)

Answer

To determine the IUPAC name of the complex ion \([CrCl_{2}(Ox)_{2}]^{3-}\), we will follow these steps:

### Step 1: Identify the ligands and their names
- The complex contains two types of ligands:
1. Chloride ions (\(Cl^-\)), which are named as "chloro."
2. Oxalate ions (\(Ox\)), which are derived from oxalic acid and are named as "oxalato."

### Step 2: Determine the oxidation state of the central metal ion
- Let the oxidation state of chromium (\(Cr\)) be \(x\).
- The charges contributed by the ligands are:
- Chloride: \(2 \times (-1) = -2\) (since there are 2 chloride ions)
- Oxalate: \(2 \times (-2) = -4\) (since there are 2 oxalate ions, each with a charge of -2)
- The overall charge of the complex is \(-3\).
- Therefore, we can set up the equation:
\[ x - 2 - 4 = -3 \]
Simplifying this gives:
\[ x - 6 = -3 \implies x = +3 \]
- Thus, the oxidation state of chromium is +3.

### Step 3: Arrange the ligands in alphabetical order
- The ligands are "chloro" and "oxalato."
- Alphabetically, "chloro" comes before "oxalato."

### Step 4: Write the name of the complex
- Since there are two chloride ligands, we use the prefix "di-" to indicate this, resulting in "dichloro."
- There are also two oxalate ligands, so we use "di-" again, resulting in "dioxalato."
- The central metal ion is chromium, and since it has a positive oxidation state, we use "chromate" instead of "chromium."
- Finally, we include the oxidation state in Roman numerals, which is +3.

### Final IUPAC Name
Putting it all together, the IUPAC name of the complex ion \([CrCl_{2}(Ox)_{2}]^{3-}\) is:
**dichlorodioxalatochromate(III)**

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