Chapter 18.docx

3 Pages
Unlock Document

Miami University
Chemistry & Biochemistry
CHM 142
Dr.James D.Garrity

Lewis Acids and bases—focuses on bond formation. Defined in terms of electron pairs, not protons  Acid—electron pair acceptor  Base—electron pair donor NH3(aq) + H2O(l)  NH4+(aq) + OH-(aq)  Bronsted-lowry o NH3=base (accepts proton) o H2O=acid (donates proton)  Lewis o NH3=base (donates electron pair) o H2O=acid (accepts electron pair) Lewis Bases are the same as Bronsted-Lowry bases Lewis Acids expand what an acid can be. Acids no longer has to have an H+ to donate  Ex. BF3 can act like a lewis acid, because it has a spot to accept an electron pair.  Metal Ions are Lewis Acids. AlCl3 + Cl-  AlCl4  AlCl3 is a Lewis Acid  Cl- is a Lewis base When you lose electrons, you take from the highest principle quantum number. So, even though 4s fills before 3d, you take from 4s not 3d hydrated metals ions as acids Ethylenediaminetetraacetic acid (EDTA)—has 6 e- pairs to donate Sequestering agent—binds the metal so tightly that the metal is unavailable to react with other substances. Polydentate ligands displace monodentate ligands because of an increase in entropy Ligands with a higher affinity for metal cation will displace ligands with less affinity Chelation effect—greater affinity of metal ions for polydentate ligands than monodentate ligands (usually) (the one with the stronger Kf value is the stronger ligand). Entropy-driven process Crystal field splitting—process of changing degenerate d-orbitals (same energy) into subsets with different energies as a result of interactions between electrons in those orbitals and lone pairs of electrons in ligands Crystal field splitting energy (Δ) Photon Energy (E) and frequency (v) are directly proportional E=hv Wavlength(λ) and frequency (v) are inversely prop
More Less

Related notes for CHM 142

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.