Which of the following is non-polar but contains polar bonds?

Options

A. HCl
B. `CO_(2)`
C. `NH_(3)`
D. `NO_(2)`

Explanation

To determine which of the following options is non-polar but contains polar bonds, we need to analyze the molecular structure and dipole moments of each option provided.

### Step-by-Step Solution:

1. **Understanding Non-Polar and Polar Bonds**:
- A molecule is considered non-polar if the net dipole moment is zero, meaning that the individual dipole moments cancel each other out.
- A polar bond occurs when there is a difference in electronegativity between the two atoms involved in the bond, resulting in a dipole moment.

2. **Analyzing Option A: HCl**:
- HCl is a diatomic molecule with a significant difference in electronegativity between hydrogen and chlorine.
- This results in a dipole moment pointing from H (partially positive) to Cl (partially negative).
- Therefore, HCl is a polar molecule (dipole moment ≠ 0).

3. **Analyzing Option B: CO2**:
- CO2 has a linear structure with carbon in the center and two oxygen atoms on either side.
- Each C=O bond is polar due to the difference in electronegativity.
- However, the two dipole moments are equal in magnitude but opposite in direction, thus they cancel each other out.
- As a result, CO2 has a net dipole moment of zero, making it a non-polar molecule despite having polar bonds.

4. **Analyzing Option C: NH3**:
- NH3 (ammonia) has a trigonal pyramidal shape due to the presence of a lone pair on nitrogen.
- The N-H bonds are polar, and the dipole moments do not cancel out due to the molecular geometry.
- Therefore, NH3 is a polar molecule (dipole moment ≠ 0).

5. **Analyzing Option D: NO2**:
- NO2 has a bent shape due to the presence of a lone pair on nitrogen.
- The N-O bonds are polar, and the dipole moments do not cancel out, resulting in a net dipole moment.
- Hence, NO2 is also a polar molecule (dipole moment ≠ 0).

### Conclusion:
The only molecule that is non-polar but contains polar bonds is **Option B: CO2**.