Which species in the given below has a coordinated bond ?

Options

A. `CH_4`
B. `SO_3^(2-)`
C. `NH_3`
D. `CO_2`

Answer

To determine which species has a coordinate bond, we will analyze the Lewis structures of the given species: CH4, SO3^2-, NH3, and CO2.

### Step-by-Step Solution:

1. **Understanding Coordinate Bonds**:
- A coordinate bond (or dative bond) is formed when one atom donates both of the electrons in a bond to another atom that has an empty orbital.

2. **Analyzing CH4 (Methane)**:
- The Lewis structure of CH4 shows that carbon shares its four valence electrons with four hydrogen atoms.
- Each bond is a covalent bond, as both atoms contribute one electron to each bond.
- **Conclusion**: CH4 does not have a coordinate bond.

3. **Analyzing SO3^2- (Sulfite Ion)**:
- The Lewis structure for SO3^2- shows sulfur bonded to three oxygen atoms.
- Sulfur has six valence electrons, and in the sulfite ion, it shares its electrons with the oxygen atoms.
- However, one of the oxygen atoms has a negative charge and can donate a pair of electrons to sulfur, forming a coordinate bond.
- **Conclusion**: SO3^2- has a coordinate bond.

4. **Analyzing NH3 (Ammonia)**:
- The Lewis structure of NH3 shows nitrogen bonded to three hydrogen atoms.
- Nitrogen has five valence electrons and shares one with each hydrogen, forming three covalent bonds.
- There is one lone pair of electrons on nitrogen, but there are no empty orbitals from another atom to accept these electrons.
- **Conclusion**: NH3 does not have a coordinate bond.

5. **Analyzing CO2 (Carbon Dioxide)**:
- The Lewis structure of CO2 shows carbon double bonded to two oxygen atoms.
- Carbon shares four electrons (two pairs) with the two oxygen atoms, which also share their electrons with carbon.
- All bonds are covalent bonds, as both atoms contribute electrons.
- **Conclusion**: CO2 does not have a coordinate bond.

### Final Answer:
The species that has a coordinate bond is **SO3^2- (Sulfite Ion)**.