Chapter 1-6 Notes: Acidity, Electron Density, and Proton Transfer (Vocabulary Flashcards)

Vocabulary flashcards covering key concepts from the notes on acidity, inductive and resonance effects, solvents, and common acid-base reactions.

Electronegativity

Atom's tendency to attract electrons in a bond; influences bond polarity and acidity.

Acidity

Tendency of a molecule to donate a proton ($$H^+$); lower pKa means a stronger acid.

Conjugate Base

Species formed when an acid donates a proton; its stability determines acid strength.

Inductive Effect

Electronic effects through sigma bonds; groups withdraw/donate electron density.

Electron Withdrawing Group (EWG)

Pulls electron density, stabilizing conjugate base and increasing acidity.

Electron Donating Group (EDG)

Donates electron density, destabilizing conjugate base and decreasing acidity.

Resonance Stabilization

Delocalization of negative charge via pi bonds; increases conjugate base stability and acid strength.

Acetate Ion ($$CH_3COO^-$)

Conjugate base of acetic acid; stabilized by resonance.

Ethoxide Ion ($$CH3CH2O^-$)

Conjugate base of ethanol; an alkoxide, generally a strong base with limited resonance.

Phenol (ArOH)

Hydroxyl group on an aromatic ring; more acidic than aliphatic alcohols due to resonance-stabilized phenoxide.

Phenoxide Ion (ArO-)

Deprotonated phenol; resonance-stabilized by the aromatic ring.

Alkoxide (RO-)

Oxygen-centered anion from alcohols; strong base with limited resonance.

Sodium Phenoxide

Salt formed when phenol is deprotonated by NaOH; phenoxide anion with Na^+.

Proton Transfer

Movement of a proton from an acid to a base.

Solvent Stabilization

Solvent molecules stabilize ions (e.g., via hydrogen bonding), affecting acidity.

Addition to a Double Bond (Electrophilic Addition)

Proton adds to a C=C bond to form a carbocation, followed by nucleophilic attack.

Tert-Butyl Alcohol to Tert-Butyl Chloride

Tert-butyl alcohol reacts with HCl; water leaves, forming tert-butyl chloride (protonation, leaving group, substitution).

pKa

Negative logarithm of the acid dissociation constant; lower pKa means a stronger acid.

Alpha vs Beta Substitution (Acidity Context)

Electronegative group at alpha position (adjacent to acidic site) has strongest effect; beta effects are smaller.