How do you identify Lewis acids and bases?

Question

Isabella Acosta · Accepted Answer

Few steps below

What you need to check for in the provided compound now is its ability to accept or donate electron pairs, for instance: #AlBr_3# Questions to be asked: #=>"Are there any unbonded electron pairs on the central atom?" =>"If yes, then this molecule can act as a Lewis Base"# #=>"Is the valence shell of the central atom filled?" =>"If not, then this molecule can act as a Lewis Acid"# With these two questions, we can determine whether this molecule is a lewis base or acid, or you can always draw a Lewis Dot structure Since one of each valence electron is bonded to each Br, the central atom, Al, has three valence electrons total. Because its valence shell is not entirely filled, the molecule can function as a Lewis acid. You try: #NH_3# #O^(-2)# #BF_3#

Delilah Anderson · Answer

undefined Lewis acids are electron-pair acceptors, while Lewis bases are electron-pair donors. In identifying Lewis acids and bases, one looks for the species that can accept or donate electron pairs during a chemical reaction. For example, metal ions, such as Al3+ or Fe2+, are Lewis acids because they can accept electron pairs from other species. Conversely, species with lone pairs of electrons, such as NH3 or OH-, are Lewis bases because they can donate electron pairs to form bonds with Lewis acids. Additionally, molecules with multiple bonds, such as CO2, can also act as Lewis acids by accepting electron pairs from Lewis bases.