States of Matter, Physical and Chemical Changes, and Elements

Vocabulary flashcards covering states of matter, physical and chemical properties and changes, chemical symbols, signs of chemical reactions, and the Law of Conservation of Matter.

Solid

A state of matter that has a definite shape and definite volume, with particles arranged in a fixed, close structure with very strong interactions that vibrate in fixed positions.

Liquid

A state of matter with a definite volume but no definite shape, where particles are arranged randomly and close together with strong interactions, moving slowly around each other to take the shape of their container.

Gas

A state of matter that takes both the shape and volume of its container, with particles arranged randomly and far apart with basically no interaction that move rapidly.

Physical Properties

Characteristics of a substance that can be observed or measured without affecting its identity, typically including shape, color, melting point, boiling point, and physical state.

Physical Change

Any change affecting a substance's state, size, or appearance without changing its composition or what the actual substance is, producing no new substances and often used to separate mixtures.

Chemical Properties

describe reactivity

are determined by a chemical reaction

Chemical Change

A change in which an original substance is converted into one or more new substances with unique properties that are different from the starting materials.

Elements

Pure substances from which all other things are built.

Chemical Symbols

Abbreviations for elements where only the first letter is capitalized; if two letters are capitalized (such as $CO$ vs $Co$), they represent two separate elements.

Phase Changes

Transitions between states of matter (such as an ice cube melting) which are always classified as physical changes.

Signs of Chemical Change

Four primary indicators that a chemical reaction has occurred: color change, temperature change or energy exchange, formation of a new phase (gas bubbles or solid precipitate), and new odor.

Precipitate

A solid formed during a chemical reaction in a liquid phase that cannot dissolve.

Exchange of Energy in Chemical Change

An indicator of a chemical change involving releasing or storing heat, or emitting light as seen in a glow stick.

Law of Conservation of Matter

A fundamental law applying to all physical and chemical changes stating that matter is neither created nor destroyed, it just changes form.

Gas Expansion Behavior

The movement of gas particles rapidly to fill the shape and volume of their container because they have little attraction to each other.