Unit 1: General Chemistry Review Concepts Flashcards

Vocabulary flashcards covering chemical representations, isomerism, Brønsted-Lowry and Lewis acid-base definitions, structural effects on acidity, and acid-base equilibrium.

Molecular formula

A chemical formula that specifies which atoms and how many of each are present in a compound.

Bond-line notation

A structural representation where the letter "C" is omitted and hydrogen atoms are usually omitted, shown only for clarity.

Isomers

Different compounds that have the exact same molecular formula.

Constitutional isomers

Isomers that differ in their atom connectivity.

Stereoisomers

Isomers that have the same atom connectivity but differ in the spatial arrangement of their atoms.

Heteroatoms

Atoms in organic chemical structures other than carbon or hydrogen, commonly including oxygen, nitrogen, sulfur, and halogens.

Brønsted-Lowry acid

A chemical species that acts as a proton donor.

Brønsted-Lowry base

A chemical species that acts as a proton acceptor.

Amphoteric

Describing a chemical structure that can act as either an acid or a base.

Amphiprotic

Describing a chemical structure that can either accept or donate a proton.

pKa and Acid Strength Relationship

Stronger acids have lower $pKa$ values, while weaker acids have higher $pKa$ values.

Conjugate Acid-Base Strength Relationship

The stronger an acid is, the weaker its conjugate base; conversely, the stronger a base is, the weaker its conjugate acid.

Inductive Effect on Acidity

Electron density shifted away from an acidic proton results in a stronger acid, whereas electron density shifted towards the atom bonded to an acidic proton results in a weaker acid.

Hybridization Effect on Acidity

An increase in the percentage of s-character in the hybridization of the atom bonded to a proton ($sp$ at 50% > $sp^2$ at 33% > $sp^3$ at 25%) increases acid strength.

Acid-Base Equilibrium Favorability

The position of equilibrium in an acid-base reaction always favors the side containing the weaker acid and weaker base.

Lewis acid

An electron pair acceptor (electrophile) that is electron deficient or possesses a bond that is easy to break.

Lewis base

An electron pair donor (nucleophile), commonly featuring species with lone pairs such as O, N, S, P, or halides.

Electrophile

An electron-deficient species or electron pair acceptor, equivalent to a Lewis acid.

Nucleophile

An electron-rich species or electron pair donor, equivalent to a Lewis base.

Adduct

The complex product formed directly from the combination of a Lewis acid and a Lewis base.