Classify the following species as Lewis acids and Lewis bases
`NH_(3), BF_(3), SnCl_(4), C_(5)H_(5)N, CO, Ni^(2+)`

Explanation

To classify the given species as Lewis acids or Lewis bases, we need to understand the definitions:

- **Lewis Acid**: A species that can accept an electron pair (electron pair acceptor).
- **Lewis Base**: A species that can donate an electron pair (electron pair donor).

Now, let's analyze each species one by one:

1. **NH₃ (Ammonia)**:
...