Chemistry Term 2 Exam Review - Bonding, Reactions, and Stoichiometry

Vocabulary flashcards covering fundamental chemistry concepts for Term 2, including bonding theories, reaction types, and stoichiometric calculations.

Octet Rule

The principle that atoms tend to gain, lose, or share electrons to achieve a full outer shell of eight valence electrons, which leads to chemical stability.

Binary Compound

A chemical compound composed of exactly two different elements.

Roman Numerals

Notation used in chemical names to indicate the specific charge of a metal cation, particularly for transition metals that can form multiple ions.

Bond Character

The nature of a chemical bond (ionic, polar covalent, or nonpolar covalent) determined by the difference in electronegativity values between the bonding atoms.

Shared Pairs (Bonding Pairs)

Pairs of electrons that are involved in the bonding between two atoms.

Unshared or Lone Pairs (Nonbonding Pairs)

Pairs of valence electrons that are not involved in bonding and are located on a single atom.

Electron Pair Repulsion

The concept that valence electron pairs surrounding an atom tend to repel each other and will therefore adopt an arrangement that minimizes this repulsion.

VSEPR

Valence Shell Electron Pair Repulsion theory; a model used to predict the geometry or molecular shapes and bond angles of molecules based on electron repulsion.

Polar Covalent Bond

A type of chemical bond where two atoms share electrons unequally.

Nonpolar Covalent Bond

A type of chemical bond where two atoms share electrons equally.

Chemical Reaction

A process in which substances (reactants) undergo chemical changes to form new substances (products).

Endothermic Reaction

A chemical reaction that absorbs energy from its surroundings.

Exothermic Reaction

A chemical reaction that releases energy into its surroundings.

Diatomic Elements

Elements that naturally exist as molecules consist of two atoms, specifically $H_2$, $N_2$, $O_2$, $F_2$, $Cl_2$, $Br_2$, and $I_2$.

Mole

A unit of measurement equal to Avogadro’s number, which is $6.02 \times 10^{23}$ particles, used to relate the number of particles to the mass of a substance.

Molar Mass

The mass of one mole of a substance, typically expressed in units of $g\,mol^{-1}$.

Stoichiometry

The study of the quantitative relationships and calculations of reactants and products in chemical reactions using balanced formula equations.

Limiting Reagent

The reactant that is completely consumed in a chemical reaction and determines the maximum amount of product that can be formed.

Excess Reagent

The reactant that remains after a chemical reaction has reached completion because the limiting reagent has been exhausted.