13.11 WED lewis acid-base model
Is an Arrhenius acid also a Lewis acid and vice-versa? what about Bronsted-lowry acids?
Arrhenius acids and Bronsted acids fall under the definition of lewis acids
Is an Arrenhius base a Lewis base? what about Bronsted-lowry bases?
Arrhenius bases and Bronsted bases fall under the definition of lewis bases.
do cations accept or donate electrons?
Cations like to accept an electron pair -don't like to donate.
When forming a complex, which molecule reacts using its LUMO?
Lewis ACID reacts using its LUMO
When forming a complex, which molecule reacts using its HOMO?
Lewis BASE reacts using its HOMO
even though O and N found on a molecule have lone pair electrons, which one would be the better lewis base site of the molecule?
Nitrogen would be the better lewis base site bc the N atom has a lower electronegativity.
what forms following the "electron pair donation"?
The electron pair that is donated serves to form a new bond between the acid and the base resulting in a new compound with a new bond.
how is an Arrhenius acid similar to the BL acid and the lewis acid?
They all have to accept electrons. An Arrhenius acid donates a proton which has to accept electrons from H2O to create H3O+ in solution. A Bronsted Lowry acid is similar, but the species accepting the proton by donating electrons don't have to be water. A Lewis acid is simply a species that accepts a pair of electrons, therefore, both the definition of an Arrhenius acid and a Bronsted Lowry acid fit under the definition of a Lewis acid.
Given the eq. expression for autoionization of water, Kw = [H3O+][OH-] what must happen to the concentration of H3O+ when the reaction occurs where OH- concentration decreases?
When the concentration of OH- decreases, the concentration of [H3O+] increases. This leads to a pH less than 7 and an acidic solution.
What must a species have to act as a Lewis base?
a lone electron pair
what is a lewis acid?
an electron pair acceptor. - has an empty atomic orbital that allows it to accept (share) an electron pair. -incomplete octet
what is a lewis base?
electron-pair donor. -has a lone pair of electrons that it can donate -no space to recieve
what is HOMO?
highest occupied molecular orbital -can donate electrons bc has weakly bound electrons -has low energy -Lewis base
when electronegativity of an atom increases, what happens to its potential as a lewis-base site?
it makes a better lewis base site
since co2 accepts an electron pair in the reaction with water, does it act as a lewis acid or base?
lewis acid
what is LUMO?
lowest unoccupied molecular orbital -can accept electrons bc doesn't contain electrons which is why its called unoccupied. -has high energy -Lewis Acid
how does solvation relate to lewis acids and bases?
the interaction can be seen as a weaker lewis acid-lewis base interaction
what is solvation?
when solvent interacts with solute that brings solute into solvent phase.
Can a single Lewis acid react with more than one Lewis base?
yes. ex. CU2+ and NH3 reacts 1:4 ratio