The shape of `[Cu(NH_3)_4]Cl_2` is:

Options

A. (a) Tetrahedral
B. (b) Octahedral
C. (c) Square planar
D. (d) Pyramidal

Explanation

To determine the shape of the coordination compound \([Cu(NH_3)_4]Cl_2\), we can follow these steps:

### Step 1: Identify the central metal ion and its oxidation state
- The complex \([Cu(NH_3)_4]Cl_2\) contains copper (Cu) as the central metal ion.
- The ammonia (NH₃) ligands are neutral, and the two chloride ions (Cl⁻) contribute a -2 charge in total.
- Therefore, to balance the -2 charge from the chlorides, copper must have a +2 oxidation state.

### Step 2: Determine the electronic configuration of the metal ion
- Copper in the +2 oxidation state has the electronic configuration of \([Ar] 3d^9\).
- This means that in the 3d subshell, there are 9 electrons.

### Step 3: Determine the coordination number
- The complex has 4 ammonia ligands coordinated to the copper ion.
- Therefore, the coordination number is 4.

### Step 4: Identify the hybridization
- For a coordination number of 4, the possible hybridizations can be \(sp^3\) or \(dsp^2\).
- In the case of copper(II) complexes, especially with a \(d^9\) configuration, the hybridization tends to be \(dsp^2\).

### Step 5: Determine the geometry
- The \(dsp^2\) hybridization leads to a square planar geometry.
- This is a common geometry for \(d^8\) and \(d^9\) metal complexes, where the ligands arrange themselves in a square planar fashion around the central metal ion.

### Conclusion
- Therefore, the shape of the complex \([Cu(NH_3)_4]Cl_2\) is square planar.

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