Step 1: Understand what a Lewis acid is. A Lewis acid is a substance that can accept an electron pair from another substance.
Step 2: Look at the options given in the question. Identify which substances are being considered.
Step 3: Check if any of the substances can accept an electron pair. For example, BF3 (boron trifluoride) has an empty p-orbital and can accept an electron pair.
Step 4: Confirm that BF3 is indeed a Lewis acid because it meets the definition of accepting an electron pair.
