Molecules and Compounds

These flashcards cover key concepts from the lecture on molecules and compounds, including definitions and examples of various chemical substances and principles.

Compound

A substance formed from two or more elements chemically bonded together in fixed proportions.

Sucrose

A compound made of carbon, hydrogen, and oxygen; commonly known as table sugar.

Law of Constant Composition

States that all samples of a given compound have the same proportions of their constituent elements.

Mass Ratio

The ratio of the masses of elements in a compound, which remains constant regardless of the sample size or origin.

Ionic Compound

A compound composed of cations (positively charged ions) and anions (negatively charged ions).

Molecular Formula

Indicates the actual number of atoms of each element in a molecule of a compound.

Empirical Formula

Gives the relative number of atoms of each element in a compound, often the simplest ratio.

Diatomic Molecule

Molecules consisting of two atoms; for example, O₂ or H₂.

Polyatomic Ion

An ion that consists of two or more atoms bonded together, acting as a single charged entity.

Nomenclature

The system of naming chemical compounds, which provides rules for identifying elements and compounds.

Acid

A molecular compound that produces H⁺ ions in solution; can be binary or oxyacid.

Hydroxide Ion

A common polyatomic ion represented as OH⁻, often found in bases.

Binary Ionic Compound

A compound consisting of just two different elements, one being a metal and the other a nonmetal.

Oxyanion

An anion that contains oxygen, such as sulfate (SO₄²⁻) or nitrate (NO₃⁻).

Chemical Formula

A symbolic representation of a compound showing the elements and their relative proportions.

Hydration

The process of adding water to a compound or the reaction of a compound with water.