CHEM231 Acid Base Reactions

conjugate acid

the particle formed when a base gains a hydrogen ion

conjugate base

the particle that remains when an acid has donated a hydrogen ion

rule of reciprocity

weak base = strong acid

strong base = weak acid

what factors and influence the strength of a conjugate base (disperse the - charge) and in what order?

electronegativity, size of the atom, resonance, induction

what happens if there is resonance in a conjugate base?

pKa value decreases: -10 for the - being on a less EN atom, -20 for same EN, -30 for greater EN

what is the formula to determine if an acid-base rxn will move forward or not

10^ (CA pka - A pKa)

what does it mean if the Ka value is > 10^-2?

rxn will move forward and depronate

what are the 3 different cutoffs for A-B rxn Ka values moving forward?

10^-2 - 10^2 (equally move forward and backward)

10^2 - 10^8 (moves forward with medium arrow back)

>10^8 (moves forward with small arrow back)

what are the 2 cutoffs for A-B rxn Ka values moving backwards?

10^-2 - 10^-8 (moves backward with medium arrow forward)

10^-8 (moves backward with small arrow forward)

formula to determine forward or backward reaction?

10^ CA pka - A pka (right - left)