The EAN of Zn in `[Zn(NH_(3))_(4)]^(2+)` is

Answer

To find the Effective Atomic Number (EAN) of zinc in the complex ion \([Zn(NH_3)_4]^{2+}\), we will follow these steps:

### Step 1: Determine the oxidation state of zinc in the complex
The overall charge of the complex ion is \(+2\). Since ammonia (NH₃) is a neutral ligand, the oxidation state of zinc (Zn) can be determined as follows:

Let the oxidation state of Zn be \(x\).
\[ x + 0 = +2 \implies x = +2 \]

### Step 2: Determine the number of electrons in the neutral zinc atom
Zinc (Zn) has an atomic number of 30, which means it has 30 electrons in its neutral state.

### Step 3: Calculate the number of electrons in the zinc ion
Since the oxidation state of zinc is \(+2\), it has lost 2 electrons:
\[ \text{Electrons in } Zn^{2+} = 30 - 2 = 28 \]

### Step 4: Determine the number of electrons donated by the ligands
Each ammonia (NH₃) ligand donates 2 electrons. In the complex \([Zn(NH_3)_4]^{2+}\), there are 4 ammonia ligands:
\[ \text{Total electrons donated by ligands} = 4 \times 2 = 8 \]

### Step 5: Calculate the Effective Atomic Number (EAN)
The EAN is calculated by adding the number of electrons in the metal ion to the number of electrons donated by the ligands:
\[ \text{EAN} = \text{Electrons in } Zn^{2+} + \text{Electrons donated by ligands} \]
\[ \text{EAN} = 28 + 8 = 36 \]

### Final Answer
The EAN of zinc in \([Zn(NH_3)_4]^{2+}\) is **36**.

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