Answer
Lewis acid: $BF_3$
Lewis base: $(CH_3)_3N$
Work Step by Step
1. Determine if each reactant can act as a Lewis acid, base or both:
- $(CH_3)_3N$: The nitrogen has, naturally, 5 electrons, and it is making 3 covalent bonds with the carbons. Therefore, there are 2 electrons that are not being used, and can be donated, making this compound a Lewis base.
- $BF_3$: The boron has, naturally, 3 electrons, and it is making 3 covalent bonds, which gives a total of 6 electrons in its valence shell.
Since this is an element from the secon row, it is capable of holding 8 electrons, which allows it to accept 2 more (8-6), making it a Lewis acid.
2. Therefore, there is only one possibility.
$(CH_3)_3N$ as a base, and $BF_3$ as an acid.
