Classification and Properties of Matter

This set of flashcards covers the classification of matter, states of matter including plasma and BEC, mixtures, pure substances, separation techniques, and physical versus chemical properties and changes.

Matter

Anything that has mass and occupies space.

Pure substance

Matter that has a uniform and unchanging composition.

Plasma

A 4th state of matter in which particles are at extremely high temperatures (over $1,000,000\,^\circ\text{C}$) and electrons are stripped away from the atom, creating positively nuclei.

Solid

A state of matter with a definite shape and volume, where particles cannot exchange positions and are incompressible.

Liquid

A state of matter with a definite volume but no fixed shape that is incompressible.

Gas

A state of matter that takes on the shape and volume of its container and is highly compressible.

Vapor

The gaseous state of a substance that is normally a solid or liquid at room temperature.

BEC (Bose-Einstein Condensate)

A state of matter formed when a gas of bosons is cooled to temperatures close to absolute zero (around $0\,K$ or $-273.15\,^\circ\text{C}$), leading to macroscopic quantum effects.

Pure Substance

A form of matter that has a definite composition and distinct properties; includes elements and compounds.

Mixture

A combination of two or more substances in which each substance retains its own distinct identity.

Heterogeneous mixture

A mixture where the composition is not uniform throughout and different components can be visibly seen.

Colloid

A type of heterogeneous mixture wherein one component (dispersed phase) is scattered throughout the other component (dispersion medium).

Suspension

A heterogeneous mixture containing large particles that tend to settle at the bottom of its container.

Homogeneous mixture (solution)

A mixture where the composition is the same throughout, consisting of a solute dissolved in a solvent.

Aqueous solution

A solution in which the solvent is water, symbolized as $(aq)$.

Miscible

Term describing two liquids that completely dissolve in each other.

Immiscible

Term describing two liquids that do not dissolve in each other.

Soluble

Term used if a substance dissolves in another substance.

Insoluble

Term used if a substance does not dissolve in another substance.

Filtration

A physical method used to separate solids from liquids.

Fractional crystallization

A method of separating two solids by adding a solvent that dissolves only one; the insoluble solid is filtered out and the solvent is evaporated to recover the other solid.

Distillation

A physical method of separating two liquids based on differences in their boiling points.

Chromatography

The separation of a mixture based on solubility in a "mobile" solvent coupled with adherence to a "stationary phase" medium like paper or silica gel.

Element

A substance that cannot be separated into simpler substances by chemical means; 114 have been identified, including 82 naturally occurring and 32 synthesized.

Compound

A substance composed of atoms of two or more different elements chemically bonded in fixed proportions.

Electrolysis

A chemical process used to separate a compound like water into its elements by passing an electric current through it.

Molecules

Structures formed when two or more neutral atoms form bonds between them by sharing electrons.

Diatomic elements

Elements that occur in nature as molecules containing two atoms: $H_2$, $N_2$, $O_2$, $F_2$, $Cl_2$, $Br_2$, and $I_2$.

Ionic compounds

Compounds composed of cations and anions held together by electrostatic attractions.

Cations

Positively charged ions that form when an atom loses electrons.

Anions

Negatively charged ions that form when an atom gains electrons.

Allotrope

One of two or more distinct molecular forms of an element, such as $O_2$ and $O_3$ for oxygen, or diamond and graphite for carbon.

Monoatomic ion

An ion that contains only one atom, such as $Na^+$, $Cl^-$, or $Ca^{2+}$.

Polyatomic ion

An ion that contains more than one atom, such as $ClO_3^-$, $NO_2^-$, or $SO_4^{2-}$.

Physical Properties

Measurable properties such as mass, density, boiling point, and solubility in water.

Chemical Properties

Properties that describe how a substance reacts with other substances, such as flammability or reactivity with water.

Extensive property

A property that depends upon how much matter is being considered and is additive, such as mass, length, or volume.

Intensive property

A property that is independent of the amount of matter being considered, such as density, melting point, or color.

Physical change

A change that does not alter the composition or identity of a substance, such as ice melting.

Chemical change (reaction)

A change that alters the identity or composition of the substance involved, evidenced by heat/light, gas production, or precipitate formation.