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Chemistry

The science that deals with matter—its composition, properties, uses, and transformations.

Matter

Anything in the universe that has mass and volume.

Mass

A measure of the amount of matter in an object.

Volume

The space occupied by a given amount of matter.

Physical Property

Anything that can be observed without changing a substance's chemical makeup.

Organoleptic Property

Anything that is observed by the senses.

Chemical Property

Anything that can be observed that alters a substance's chemical makeup.

Boiling Point

The temperature at which a substance changes from a liquid to a gas.

Melting Point

The temperature at which a substance changes from a solid to a liquid.

Pure Substance

A substance that is uniform throughout its chemical composition and properties.

Element

A pure substance that cannot be broken down into simpler substances chemically.

Compound

A pure substance that can be broken down into simpler substances by chemical reactions.

Homogenous Mixture

A uniform mixture that has the same composition throughout with indistinguishable parts.

Heterogenous Mixture

A non-uniform mixture with regions of different composition and distinguishable parts.

Extraction

Separating a solid mixture by selectively dissolving one component.

Distillation

Separating components within a liquid mixture through boiling at various temperatures.

Chromatography

Separating components within a liquid mixture by partition between two phases (liquid and solid).

Filtration

Pouring a solid-liquid mixture through a filter to separate heterogeneous mixtures.

Decantation

Pouring a liquid over a solid that has settled.

Exothermic Reaction

A chemical reaction where energy is released (Delta is on the right).

Endothermic Reaction

A chemical reaction where energy is absorbed (Delta is on the left).

Law of Conservation of Mass and Energy

Mass and energy cannot be created or destroyed, only transformed.

Measured Numbers

Numbers obtained from a measuring device with a small error or uncertainty.

Exact Numbers

Numbers determined by counting or definition without error, having infinite significant figures.

Sig Fig Multiplication and Division Rule

The number in the operation with the fewest significant figures dictates the sig figs in the answer.

Sig Fig Addition and Subtraction Rule

The number in the operation with the fewest decimal places dictates the sig figs in the answer.

Scientific Notation for Numbers Greater Than 1

Move the decimal left until reaching a number between 1 and 9, and use a positive exponent.

Scientific Notation for Numbers Less Than 1

Move the decimal right until reaching a number between 1 and 9, and use a negative exponent.

Dimensional Analysis

A technique that allows problem-solving using the factor label method for unit conversions.

Joule (J)

The SI unit for energy.

Calorie (cal)

A metric unit for energy, where 1 cal = 4.184 J.

Specific Gravity

The density of a substance divided by the density of water at the same temperature.

Volume by Displacement

Determining the volume of an oddly shaped object by measuring the rise in water level.