Bronsted Acid and Bases, pKa, C-A-R-I-O, Lewis Acid and Bases Flashcards
Arrhenius Acid
Substance when add an water, increase the concentration of H3O+ in solution
Arrhenius Base
Substance when add to water, increase the concentration of OH- ion in solution
Bronsed Lowry Acid
Anything that releases proton
Bronsted Lowry Base
Anything that accepts proton
Conjugate Acid
Product that result when a base accept a proton
Conjugate Base
Product that results when a base gains a proton
What does equilibrium always favor?
Equilibrium always favor formation of weaker acid and base
Why does equilibrium favor the weak acid and weak base?
The weaker acid and the weaker base are the most stable species due to their lower potential energies.
What determines the strength of a bronsted acid?
how much they can dissociate in solution to release H+ and their conjugate base
How do you tell the strength of an acid based on their pKa?
Lower the pKa, stronger the acid
What type of strength relationship is between acid/base and conjugate acid/conjugate base?
Inverse relationship.
The stronger the acid, the weaker its conjugate base.
The stronger the base, the weaker its conjugate acid
Why does acid/base have in inverse relationship of strength than its conjugate pairs?
If an acid is strong, it will readily donate its hydrogen. Thus, its conjugate acid, the substance that results from the loss of proton, did not hold the proton very well, thus weak.
How does charge affect acid strength?
The more positively charged an atom is, the stronger its acidity is. There is more hydronium ion, making the compound more acidic.
How does electronegative affect acid strength?
Atom Effect - Electronegativity: The proton that is attached to a more electronegative atom is more negative
How does atomic size affect acid strength?
The proton that is attached to a bigger atom is more acidic.
How does resonance effect affect acid strength?
The acid with a conjugate base that is stabilized by resonance structure will be more acidic
How does inductive effect affect acid strength?
The proton that is near an electron withdrawing group (EWG) is more acidic.
Number and Distance of EWG: As the number of EWG increase, the more acidic the proton
As the distance of the EWG from the acid proton increase, the less acidic
How does orbital effect affect acid strength?
As the s character of the hybridized carbon increases, the more acidic the attached proton is
What is a lewis acid?
Substance that accept electron pairs
Lewis Bases
Substances that donate electron pairs
What is an electrophile?
Molecule that forms a bond by accepting a lone pair from another molecule (nucleophile)
Usually positively charge so it’s “electron-loving”
What is a nucleophile?
An atom or molecule that form a bond by donating a pair of electrons.
A nucleophile wants to seek a positively charged nucleus to form a bond with its negatively charged polar. Therefore, nucleophile always initiate bonding with electrophile. Usually neutral or negatively charged.