Unit 1: Matter and Change, Classification of Matter, & Metals, Metalloids and Non-metals

Chemistry

The study of the composition, structure, and properties of matter, the processes it undergoes, and associated energy changes.

Matter

Anything that has mass and occupies space (volume).

Mass

A measure of the amount of matter in an object.

Atoms and Molecules

Tiny particles that compose all matter; atoms bind together using chemical bonds to form molecules.

Organic Chemistry

The study of carbon-containing compounds.

Inorganic Chemistry

The study of non-organic substances.

Physical Chemistry

The study of properties and changes of matter and their relation to energy.

Analytical Chemistry

The identification of components and composition of materials.

Biochemistry

The study of substances and processes occurring in living things.

Theoretical Chemistry

The use of math and computers to understand chemical principles and design new compounds.

Extensive Property

A property that depends on the amount of matter present (e.g., mass, volume, length).

Intensive Property

A property that does NOT depend on the amount of matter present (e.g., density, temperature, color).

Physical Property

A characteristic that can be observed or measured without changing the identity of the substance.

Physical Change

A change in a substance that does not involve altering its chemical identity (e.g., phase change, shape change).

States of Matter (Solid, Liquid, Gas)

Solid: definite volume and shape. Liquid: definite volume, indefinite shape. Gas: no definite volume or shape.

Plasma

A high-temperature physical state of matter in which atoms lose most of their electrons.

Solute vs. Solvent

The solute is the substance that gets dissolved; the solvent is the substance that does the dissolving.

Saturated Solution

A solution holding the maximum amount of dissolved solute possible at that temperature.

Chemical Property

Relates to a substance's ability to undergo changes that transform it into different substances (e.g., flammability, ability to rust).

Chemical Change

A change in which one or more substances are converted into different substances (also called a chemical reaction).

Law of Conservation of Mass

Matter cannot be created or destroyed during chemical or physical changes.

Evidence of a Chemical Change

Formation of gas, temperature/heat change, formation of a precipitate, color change, or odor change.

Exothermic vs. Endothermic

Exothermic reactions release energy and feel warm; endothermic reactions absorb energy and feel cold.

Periodic Table Groups (Families)

Vertical columns on the periodic table containing elements with similar properties.

Periodic Table Periods

Horizontal rows on the periodic table where physical and chemical properties change regularly.

Metals

Found on the left side of the periodic table; typically good conductors, malleable, ductile, and have high melting points.

Nonmetals

Found on the right side of the periodic table; poor conductors, dull, brittle, and many are gases at room temperature.

Metalloids

Found along the staircase line; semiconductors with characteristics of both metals and nonmetals.

Heterogeneous Matter

Matter that is not uniform throughout and is composed of more than one phase, with each part retaining its own identity.

Homogeneous Matter

Matter that is uniform throughout, composed of only one phase with the same proportion of components.

Solution

A homogeneous mixture with a variable composition consisting of a solute uniformly scattered in a solvent.

Pure Substance

Matter that has a constant composition and the same characteristic properties throughout every sample.

Compound

A pure substance made of two or more elements joined by chemical bonds that can be decomposed by chemical change.

Element

A pure substance made of only one kind of atom that cannot be broken down into simpler substances.

Phase

A physically separate region or part of a material.

Interface

The boundary separating different phases in a heterogeneous material.