Classify the following into Lewis acids and Lewis bases
` NH_3,BF_3 , Ag^(+) , SiF_4 , CO_2,C_2H_5OH, CH_3NH_2,Ni^(2+) `

Answer

To classify the given substances into Lewis acids and Lewis bases, we first need to understand the definitions of Lewis acids and bases:

- **Lewis Acid**: A species that can accept an electron pair. These are typically electron-deficient species or positively charged ions.
- **Lewis Base**: A species that can donate an electron pair. These usually have lone pairs of electrons available for donation.

Now, let's classify each of the given substances:

1. **NH₃ (Ammonia)**:
- Ammonia has a nitrogen atom with a lone pair of electrons. It can donate this lone pair.
- **Classification**: Lewis Base

2. **BF₃ (Boron Trifluoride)**:
- Boron in BF₃ has an incomplete octet (only 6 electrons). It can accept an electron pair to complete its octet.
- **Classification**: Lewis Acid

3. **Ag⁺ (Silver Ion)**:
- The silver ion has a positive charge and can accept electrons.
- **Classification**: Lewis Acid

4. **SiF₄ (Silicon Tetrafluoride)**:
- Silicon can expand its octet due to the presence of empty d orbitals, allowing it to accept electron pairs.
- **Classification**: Lewis Acid

5. **CO₂ (Carbon Dioxide)**:
- In CO₂, the carbon atom has a partial positive charge, making it capable of accepting electron pairs.
- **Classification**: Lewis Acid

6. **C₂H₅OH (Ethanol)**:
- The oxygen atom in the hydroxyl group (-OH) has lone pairs that can be donated.
- **Classification**: Lewis Base

7. **CH₃NH₂ (Methylamine)**:
- Similar to ammonia, methylamine has a nitrogen atom with a lone pair that can be donated.
- **Classification**: Lewis Base

8. **Ni²⁺ (Nickel Ion)**:
- The nickel ion is positively charged and can accept electron pairs.
- **Classification**: Lewis Acid

### Summary of Classifications:
- **Lewis Bases**: NH₃, C₂H₅OH, CH₃NH₂
- **Lewis Acids**: BF₃, Ag⁺, SiF₄, CO₂, Ni²⁺