Which of the following species is non- polar ?

Options

A. trans - pent - 2 - ene
B. cis - pent - 2 - ene
C. cis - 1 - chloropropene
D. `SF_6`

Answer

To determine which of the given species is non-polar, we need to analyze the molecular structures and their dipole moments. Let's go through the options step by step.

### Step 1: Analyze Trans-Pent-2-ene
1. **Structure**: Trans-pent-2-ene has a double bond between the second and third carbon atoms, with CH3 groups on one side and CH2CH3 on the other.
2. **Polarity**: The presence of different groups (CH3 and CH2CH3) means that the dipole moments will not cancel out. Therefore, trans-pent-2-ene is **polar**.

### Step 2: Analyze Cis-Pent-2-ene
1. **Structure**: Cis-pent-2-ene also has a double bond between the second and third carbon atoms, but both CH2CH3 groups are on the same side.
2. **Polarity**: Similar to trans-pent-2-ene, the dipole moments from the two CH2CH3 groups will not cancel out. Thus, cis-pent-2-ene is also **polar**.

### Step 3: Analyze Cis-1-Chloropropene
1. **Structure**: Cis-1-chloropropene has a chlorine atom attached to the first carbon of the propene chain.
2. **Polarity**: Chlorine is more electronegative than carbon, creating a dipole moment. Since the dipole moments do not cancel out, cis-1-chloropropene is **polar**.

### Step 4: Analyze SF6 (Sulfur Hexafluoride)
1. **Structure**: SF6 has a sulfur atom at the center with six fluorine atoms surrounding it in an octahedral geometry.
2. **Polarity**: The symmetry of the SF6 molecule means that the dipole moments from each fluorine atom cancel each other out completely. Therefore, the net dipole moment (mu net) is zero, making SF6 **non-polar**.

### Conclusion
The species that is non-polar among the options provided is **SF6 (Sulfur Hexafluoride)**.

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