How many among the following species can be classified as Lewis acids?
`overset(o+)(CH_(3)), Cl^(o+),CO_(2), "CCl"_(2), BCl_(3), BI_(3), Fe^(+2), AlCl_(3)`

Answer

To determine how many of the given species can be classified as Lewis acids, we need to identify which species can accept a lone pair of electrons. A Lewis acid is defined as a substance that can accept an electron pair.

Let's analyze each species one by one:

1. **CH₃⁺ (Methyl cation)**:
- Carbon in CH₃⁺ has only three hydrogen atoms and a positive charge, indicating it has an empty p-orbital. Thus, it can accept a lone pair of electrons.
- **Conclusion**: CH₃⁺ is a Lewis acid.

2. **Cl⁺ (Chloronium ion)**:
- Chlorine has 7 valence electrons. In Cl⁺, it loses one electron, leaving it with an empty p-orbital. Therefore, it can accept a lone pair.
- **Conclusion**: Cl⁺ is a Lewis acid.

3. **CO₂ (Carbon dioxide)**:
- In CO₂, carbon is sp hybridized and has two double bonds with oxygen. The carbon atom can accept a lone pair of electrons due to the presence of empty p-orbitals.
- **Conclusion**: CO₂ is a Lewis acid.

4. **CCl₂ (Dichlorocarbene)**:
- CCl₂ has two chlorine atoms and a carbon atom with a lone pair of electrons. The carbon atom can accept a lone pair due to its empty p-orbital.
- **Conclusion**: CCl₂ can act as a Lewis acid.

5. **BCl₃ (Boron trichloride)**:
- Boron has only three valence electrons and forms three bonds with chlorine, leaving it with an empty p-orbital. It can accept a lone pair of electrons.
- **Conclusion**: BCl₃ is a Lewis acid.

6. **BI₃ (Boron triiodide)**:
- Similar to BCl₃, boron in BI₃ has an empty p-orbital after forming three bonds with iodine. It can accept a lone pair.
- **Conclusion**: BI₃ is a Lewis acid.

7. **Fe²⁺ (Iron(II) ion)**:
- Iron in the +2 oxidation state has an empty 4s orbital and can accept electron pairs.
- **Conclusion**: Fe²⁺ is a Lewis acid.

8. **AlCl₃ (Aluminum chloride)**:
- Aluminum in AlCl₃ has an empty p-orbital after forming three bonds with chlorine. It can accept a lone pair of electrons.
- **Conclusion**: AlCl₃ is a Lewis acid.

Now, let's summarize the findings:
- CH₃⁺: Lewis acid
- Cl⁺: Lewis acid
- CO₂: Lewis acid
- CCl₂: Lewis acid
- BCl₃: Lewis acid
- BI₃: Lewis acid
- Fe²⁺: Lewis acid
- AlCl₃: Lewis acid

**Total count of Lewis acids**: 8

### Final Answer:
**8 species can be classified as Lewis acids.**