General Chemistry I – Matter

Vocabulary flashcards covering foundational terms and definitions from the General Chemistry I lecture notes.

Chemistry

The science that studies the composition, structure, properties, and reactions of matter.

Matter

Anything that occupies space and has mass.

Pure Substance

A homogeneous material consisting of only one kind of matter with a definite, fixed composition.

Element

A pure substance that cannot be decomposed into simpler substances by chemical means; represented by a symbol.

Metal

An element that is typically shiny, malleable, and a good conductor of heat and electricity (e.g., Fe, Au, Al).

Non-metal

An element that lacks metallic properties, often brittle and poor conductor (e.g., C, H, O).

Metalloid

An element with properties intermediate between metals and non-metals (e.g., B, Si, As).

Compound

A substance composed of two or more elements chemically combined in definite proportions; can be decomposed chemically.

Organic Compound

A compound that contains carbon atoms.

Inorganic Compound

A compound that does not contain carbon atoms.

Acid

A substance that releases H⁺ ions in solution, turns blue litmus red, and tastes sour.

Base

A substance that releases OH⁻ ions in solution, turns red litmus blue, and tastes bitter.

Salt

An ionic compound that shows no characteristic acid or base reaction with litmus and tastes salty.

Covalent Compound

A compound whose constituent elements are bonded by sharing electrons.

Ionic (Electrovalent) Compound

A compound whose constituent elements are bonded by transfer of electrons.

Electrolyte

A compound whose aqueous solution or molten state conducts electricity.

Nonelectrolyte

A compound whose solution does not conduct electricity.

Mixture

A combination of two or more elements and/or compounds that retain their individual chemical identities.

Homogeneous Mixture

A mixture whose components are uniformly distributed and indistinguishable from one another.

Heterogeneous Mixture

A mixture whose components are not uniformly distributed and are distinguishable.

Solid

State of matter with tightly packed particles vibrating about fixed positions; definite shape and volume.

Liquid

State of matter with closely packed particles that slide past one another; definite volume but indefinite shape.

Gas

State of matter with widely separated, freely moving particles; indefinite shape and volume.

Plasma

Ionized gas containing free-floating ions and electrons that conducts electricity; discovered by William Crookes (1879).

Kinetic Theory of Matter

Theory stating that matter is made of particles in continual random motion.

Physical Property

An inherent characteristic of a substance observed without changing its composition.

Extensive (Extrinsic) Property

Physical property that depends on the amount of material (e.g., mass, volume, length).

Intensive (Intrinsic) Property

Physical property that depends on the kind of material, not the amount (e.g., density, melting point).

Chemical Property

The ability of a substance to form new substances by reaction or decomposition (e.g., iron rusting).

Physical Change

A change in physical properties or state that does not alter the substance’s composition.

Chemical Change

A transformation that produces new substances with properties different from the original; also called a chemical reaction.

What are free-floating ions?

These are atoms stripped of some positively charged electrons. It conducts electric current as well.