The geometry of the atoms in the species `PCl_4^+` is best described as

Options

A. tetrahedral
B. see saw
C. square
D. trigonal bipyramidal

Answer

To determine the geometry of the species \( PCl_4^+ \), we can follow these steps:

### Step 1: Determine the Valence Electrons
Phosphorus (P) has 5 valence electrons in its outermost shell. Chlorine (Cl) has 7 valence electrons. In \( PCl_4^+ \), phosphorus loses one electron due to the positive charge, leaving it with 4 valence electrons.

**Hint:** Count the valence electrons of each atom and consider the effect of the positive charge on the central atom.

### Step 2: Identify Bonding Electrons
Since phosphorus has 4 valence electrons remaining, it can form 4 bonds with 4 chlorine atoms. Each bond uses one of phosphorus's valence electrons.

**Hint:** Remember that each bond formed with chlorine involves one valence electron from phosphorus.

### Step 3: Determine Lone Pairs
After forming 4 bonds with chlorine, phosphorus has no lone pairs left. Therefore, all 4 valence electrons are involved in bonding.

**Hint:** Check how many valence electrons are used for bonding and how many are left as lone pairs.

### Step 4: Determine Hybridization
With 4 bonding pairs and no lone pairs, the hybridization of phosphorus in \( PCl_4^+ \) is \( sp^3 \).

**Hint:** Use the number of bonding pairs and lone pairs to determine the hybridization.

### Step 5: Determine Molecular Geometry
The geometry corresponding to \( sp^3 \) hybridization with no lone pairs is tetrahedral.

**Hint:** Recall the VSEPR theory, which relates hybridization to molecular geometry.

### Conclusion
The geometry of the atoms in the species \( PCl_4^+ \) is best described as **tetrahedral**.

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