Question

${BF}_3$ and ${NH}_3$ undergo a Lewis acid-base reaction forming an adduct. Which picture below currently represents the curved arrow notation for the initial Lewis acid-Lewis base interaction in this reaction, what is the Lewis acid and the Lewis base?

• A. Picture (1) is correct; ${NH}_3$ is the Lewis acid and ${BF}_3$ is the Lewis base.
• B. Picture (2) is correct; ${BF}_3$ is the Lewis acid and ${NH}_3$ is the Lewis base.
• C. Picture (3) is correct; ${NH}_3$ is the Lewis acid and ${BF}_3$ is the Lewis base.
• D. Picture (4) is correct; ${BF}_3$ is the Lewis acid and ${NH}_3$ is the Lewis base.

Answer 1

Answer: (B)

Picture (2) is correct; ${BF}_3$ is the Lewis acid and ${NH}_3$ is the Lewis base.

Since $B$ haas a vacant orbital $N{H}_3$ gives electron to Baron and undergoes a Lewis acid base reactions.

So, $BF$ is a Lewis acid and $N{H}_3$ is a Lewis base.