[smileshaikh]

Here are examples from my book... I've tried to find out online but I do not understand technical terms, so if you could please explain it to me in baby language that would be great.

Which of the following are likely to act as Lewis Acids and which as Lewis Bases?
a) AlBr3
b) CH3CH2NH2
c) BH3
d) HF
e) CH3SCH3
f) TiCl4

I'm not looking for the answers, but just how to do them and where to start. I have 0% idea how to do this. All I know is that lewis acids accept electron pairs and lewis bases donate electron pair.

If you could at least explain one of these, that would be great.

How do you determine which one acts as a lewis acid or base when there aren't charges written on the elements?

Thanks...

[Unknown008]

Take the first one,



Aluminium can accommodate for 8 outer electrons. It itself has three electrons, and like you probably know that aluminium bromide is a covalent compound, it gets three other electrons, one from each bromine atom. This leaves one vacant orbital around the aluminium atom (which can hold up to 2 electrons) and hence makes it an electron acceptor. As such, it is a Lewis acid.

Can you at least try the others and say what you think they would be?

[kINGkUNAL]

Basically,
Lewis acid is formed by accepting electrons..
And this is only possible if and only if it has a vacant orbital..
Therefore molecules with incomplete octet act as lewis acid..

Lewis base are formed by donating electrons..
And it is possible if it has an extra electronic pair..
For better understanding..
Form a Lewis structure..
And observe the following...

[molecule101]

(b) CH3CH2NH2 - Lewis base

Nitrogen has two extra pair of electrons which may be available for any electrophile for bonding and making nitrogen a positively charged atom