Which of the following compounds has a zero dipole momnet ? .

Options

A. 1,1-Dichloroethylene
B. cis-1,2Dicloroehtylene
C. trans-1,2-Dichloroethylene
D. None of these

Explanation

To determine which of the following compounds has a zero dipole moment, we need to analyze the molecular structure and the arrangement of dipole moments in each compound. Here’s a step-by-step solution:

### Step 1: Understand Dipole Moment
The dipole moment is a vector quantity that depends on the difference in electronegativity between atoms and the geometry of the molecule. A molecule will have a net dipole moment if the individual dipole moments do not cancel each other out.

### Step 2: Analyze 1,1-Dichloroethylene
- **Structure**: The structure of 1,1-dichloroethylene has two chlorine atoms attached to the same carbon atom.
- **Dipole Moments**: The dipole moments from the two C-Cl bonds will point in the same direction.
- **Conclusion**: The net dipole moment is not equal to zero, indicating that this molecule is polar.

### Step 3: Analyze Cis-1,2-Dichloroethylene
- **Structure**: In cis-1,2-dichloroethylene, the two chlorine atoms are on the same side of the double bond.
- **Dipole Moments**: The dipole moments from the C-Cl bonds will add up in the same direction.
- **Conclusion**: The net dipole moment is not equal to zero, indicating that this molecule is also polar.

### Step 4: Analyze Trans-1,2-Dichloroethylene
- **Structure**: In trans-1,2-dichloroethylene, the chlorine atoms are on opposite sides of the double bond.
- **Dipole Moments**: The dipole moments from the C-Cl bonds will point in opposite directions and will cancel each other out.
- **Conclusion**: The net dipole moment is equal to zero, indicating that this molecule is nonpolar.

### Final Answer
The compound that has a zero dipole moment is **Trans-1,2-Dichloroethylene**.

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