Which of the following is a correct statement ?

Options

A. All molecules with polar bond have dipole moment
B. `SnCl_(2)` is non-linear molecule
C. Dipole moment of `CH_(3)Cl` is greater than `CH_(3)F`
D. `I_(3)^(-)` has linear shape

Answer

To determine which of the statements is correct, we will analyze each option step by step.

### Step 1: Analyze Statement 1
**Statement:** All molecules with a polar bond have a dipole moment.

**Analysis:**
- This statement is incorrect. A molecule can have polar bonds but still have a net dipole moment of zero if the molecular geometry is symmetrical.
- **Example:** BF3 (Boron Trifluoride) has polar bonds (B-F), but the molecule is symmetrical (trigonal planar), leading to the cancellation of dipole moments. Therefore, the overall dipole moment is zero.

### Step 2: Analyze Statement 2
**Statement:** SnCl2 is a non-linear molecule.

**Analysis:**
- This statement is correct. SnCl2 (Tin(II) Chloride) has a bent shape due to the presence of a lone pair on the tin atom.
- The molecular geometry is non-linear, confirming that SnCl2 is indeed a non-linear molecule.

### Step 3: Analyze Statement 3
**Statement:** The dipole moment of CH3Cl is greater than that of CH3F.

**Analysis:**
- This statement is incorrect. Although CH3Cl (Chloromethane) has a polar bond, the electronegativity difference between C and Cl is less than that between C and F.
- The dipole moment is influenced by both the charge (due to electronegativity difference) and the bond length. The C-F bond is shorter and more polar than the C-Cl bond, resulting in a greater dipole moment for CH3F than for CH3Cl.

### Step 4: Analyze Statement 4
**Statement:** I3- has a linear shape.

**Analysis:**
- This statement is correct. The I3- ion consists of three iodine atoms, with one iodine atom in the center and two terminal iodine atoms.
- The central iodine atom forms two bonds with the terminal iodine atoms and has three lone pairs, leading to a linear geometry due to the arrangement of the bonding pairs and lone pairs.

### Conclusion
- The correct statements are:
- **Statement 2:** SnCl2 is a non-linear molecule.
- **Statement 4:** I3- has a linear shape.

### Final Answer:
The correct statements are:
- SnCl2 is a non-linear molecule.
- I3- has a linear shape.