The true statement from the following are

Options

A. `PH_(5),NCl_(5)` and `BiCl_(5)` do not exist
B. `I_(3)^(-)` has bent geometry
C. `XeF_(4)` is polar molecule
D. `O_(2)` and `O_(2)^(-2)` has same bond order

Answer

To determine the true statements from the given options, we will analyze each statement one by one.

### Step 1: Analyze the first statement - "PH5, NCl5, and BiCl5 do not exist."
- **PH5**: Phosphorus (P) can utilize its s, p, and d orbitals for bonding. However, due to the small size of hydrogen, the d-orbitals of phosphorus cannot effectively overlap with hydrogen's orbitals, making the formation of PH5 impossible.
- **NCl5**: Nitrogen (N) has an atomic number of 7, and its small size limits it to forming a maximum of three bonds (as seen in NH3). Therefore, N cannot form five bonds, making NCl5 non-existent.
- **BiCl5**: Bismuth (Bi), being larger than nitrogen and chlorine, experiences steric hindrance due to its size and the size of chlorine atoms. This steric hindrance prevents the formation of BiCl5.
- **Conclusion**: The first statement is true.

### Step 2: Analyze the second statement - "I3- has bent geometry."
- **I3-**: The ion consists of three iodine atoms. The central iodine atom is bonded to two terminal iodine atoms. The geometry of I3- is linear due to the arrangement of the three iodine atoms and the presence of a negative charge, which does not affect the linearity.
- **Conclusion**: The second statement is false.

### Step 3: Analyze the third statement - "XeF4 is a polar molecule."
- **XeF4**: Xenon (Xe) has 8 valence electrons. In XeF4, there are four fluorine atoms bonded to xenon, and two lone pairs of electrons on xenon. The symmetrical arrangement of the four fluorine atoms around xenon leads to the cancellation of dipole moments, resulting in a non-polar molecule.
- **Conclusion**: The third statement is false.

### Step 4: Analyze the fourth statement - "O2 and O2 2- have the same bond order."
- **O2**: Molecular oxygen has a bond order of 2 (double bond).
- **O2 2-**: The peroxide ion has two additional electrons, leading to a bond order of 1 (single bond).
- **Conclusion**: The fourth statement is false.

### Final Conclusion:
The only true statement is the first one: "PH5, NCl5, and BiCl5 do not exist."

---