Module 1: Matter and Its Laws

Flashcards covering the states of matter, classification of substances, properties and changes in matter, and the fundamental laws of chemical combination.

Matter

Anything that occupies space and has mass.

Solid

A state of matter where particles are closely packed in fixed positions, giving it a definite shape and volume with motion limited to vibrations.

Liquid

A state of matter where particles remain close together but are not fixed in place, allowing it to flow and assume the shape of its container while maintaining a definite volume.

Gas

A state of matter where particles are far apart and move freely, resulting in neither definite shape nor volume, and high compressibility.

Plasma

An additional state of matter described as ionized gas with free-moving charged particles.

Bose-Einstein condensates

A state of matter formed at extremely low temperatures where particles occupy the same quantum state.

Pure Substances

Substances that consist of only one type of particle, have a definite and constant composition, and have properties that are always the same under the same conditions.

Elements

The simplest form of matter that cannot be broken down into simpler substances by chemical or physical means; there are $118$ known elements.

Compounds

Substances formed by the chemical combination of two or more elements in fixed proportions, such as $\text{H}_2\text{O}$ or $\text{NaCl}$, which can be broken down only by chemical means.

Mixtures

Physical combinations of two or more substances where each retains its own properties and the composition can vary.

Homogeneous Mixtures (Solutions)

Mixtures with a uniform composition throughout where components are not visibly distinguishable, such as salt dissolved in water.

Heterogeneous Mixtures

Mixtures with a non-uniform composition and two or more visible phases, such as sand in water or oil and vinegar.

Physical Properties

Characteristics that can be observed or measured without changing the composition of the material, including melting point ($mp$), boiling point ($bp$), and solubility.

Intensive Property

A characteristic of matter that does not depend on the amount of substance present, such as density and color.

Extensive Property

A characteristic of matter that depends on the amount of matter being measured, such as mass and volume.

Physical Change

A transformation that alters a substance without changing its composition, most commonly seen in changes of state like melting or boiling.

Chemical Properties

Properties that determine how a substance can be converted to another substance, such as reactivity, flammability, and $\text{pH}$.

Chemical Change

Also known as a chemical reaction, this process converts one material into another with a different composition, such as the conversion of hydrogen and oxygen to water.

Law of Conservation of Mass

A principle stating that matter is neither created nor destroyed during a chemical reaction, so the total mass of reactants equals the total mass of products.

Law of Definite Proportions

Also known as the Law of Constant Composition, it states that a pure chemical compound always contains the same elements combined in the same fixed ratio by mass.

Law of Multiple Proportions

A law stating that when two elements form more than one compound, the masses of one element that combine with a fixed mass of the other are in small whole-number ratios.