Unit 1: Chemistry - The Nature of Matter

Comprehensive vocabulary flashcards covering the nature of matter, particle theory, classification of substances, the scientific method, laws of matter, the periodic table, physical/chemical properties, Bohr-Rutherford models, and environmental impacts of consumer products.

Chemistry

The study of matter, changes in matter, and how different substances combine and interact with each other.

Central Science

A moniker given to chemistry because an understanding of it is essential for fully understanding physics and biology.

Matter

Anything that has mass and takes up volume (occupies space).

Atom

The basic unit of a chemical element consisting of protons, neutrons, and electrons.

Mass

A measure of the total amount of matter contained in an object.

Volume

The amount of three-dimensional space that an object or substance occupies.

Solid

A state of matter where particles are packed tightly together in a fixed shape and do not flow or conform to their container unless an external force is applied.

Liquid

A state of matter that has no definite shape, whose particles are close together but free to flow and take the shape of their container.

Gas

A state of matter consisting of particles that are widely separated, move freely at high speeds, and expand to fill the entire volume of their container.

Melting

The change of state in which a solid transforms into a liquid.

Freezing

The change of state in which a liquid transforms into a solid.

Evaporation

The change of state in which a liquid transforms into a gas.

Condensation

The change of state in which a gas transforms into a liquid.

Sublimation

The change of state in which a solid transforms directly into a gas without passing through the liquid phase.

Deposition

The change of state in which a gas transforms directly into a solid without passing through the liquid phase.

Particle Theory

A scientific theory explaining that all matter is made of particles that are always moving, have spaces between them, move faster when heated, and are identical within any given pure substance.

Pure Substance

A type of matter that contains only one specific kind of particle throughout, existing either as an element or as a compound.

Element

A pure substance consisting of only a single kind of atom that cannot be chemically broken down into simpler substances.

Compound

A pure substance formed when two or more different chemical elements combine chemically in fixed proportions.

Mixture

A physical combination of two or more pure substances that retain their identities and can be separated by physical means.

Heterogeneous Mixture (Mechanical Mixture)

A mixture whose composition is non-uniform, allowing the individual distinct substances or phases to be seen and separated.

Homogeneous Mixture (Solution)

A mixture in which two or more pure substances combine uniformly such that the composition is identical throughout.

Solute

The substance that is dissolved into a solvent to form a solution.

Solvent

The substance in a solution that does the dissolving of the solute.

Universal Solvent

A title given to water ($H_2O$) because of its capacity to dissolve more substances than any other known liquid.

Saturated Solution

A solution that holds the maximum amount of solute that can be completely dissolved at a specified temperature.

Unsaturated Solution

A solution containing less dissolved solute than its capacity at a given temperature, allowing additional solute to dissolve.

Quarks

Elementary subatomic particles that make up protons and neutrons, held together by gauge bosons called gluons.

Scientific Law

A scientific statement that predicts, describes, and summarizes observable natural phenomena without attempting to explain why they occur.

Scientific Theory

A well-substantiated explanation that explains why a natural phenomenon happens the way it does.

Scientific Model

A physical, conceptual, or mathematical representation used to visualize, simulate, and understand complex systems, events, or processes.

Scientific Method

A systematic investigation procedure comprising observation, question formulation, hypothesis development, experimentation, data analysis, drawing conclusions, and communicating results.

Reliability

The extent to which an experimental measurement or test yields consistent and reproducible results under identical conditions.

Validity

The degree to which an experimental method accurately measures what it was intended to evaluate.

Law of Conservation of Mass

A fundamental law stating that in any chemical reaction, the total mass of the reactants is always equal to the total mass of the products.

Law of Definite Composition

A law stating that any chemical compound always contains exactly the same proportion of elements by mass.

Law of Multiple Proportions

A law stating that when two elements combine to form more than one compound, the ratios of the masses of the second element that combine with a fixed mass of the first are small whole numbers.

Periodic Table of Elements

A tabular arrangement of all chemical elements ordered by increasing atomic number and organized into groups and periods according to their recurring physical and chemical properties.

Dmitri Mendeleev

The Russian chemist who designed the first periodic table in 1869 by arranging the 63 known elements in order of increasing atomic mass.

Atomic Number

The total number of protons located within the nucleus of an atom, defining the identity of a chemical element.

Atomic Mass

The mass of an atom of a chemical element expressed in atomic mass units, from which the average number of neutrons is found by subtracting the atomic number.

Metals

Elements typically situated on the left and center of the periodic table that are lustrous, dense, malleable, ductile, possess high melting points, and conduct heat and electricity efficiently.

Nonmetals

Elements that are dull, brittle, and poor conductors of heat and electricity.

Metalloids

Elements situated between metals and nonmetals on the periodic table that exhibit intermediate properties of both.

Alkali Metals

A chemical family of elements in Group 1 of the periodic table that are extremely reactive and readily bond with other elements or compounds.

Alkaline Earth Metals

A family of greyish-white, metallic elements located in Group 2 of the periodic table that are good conductors and highly reactive, though less reactive than alkali metals.

Halogens

A chemical family in Group 17 consisting of six reactive non-metallic elements that span all three states of matter (solid, liquid, gas) at room temperature.

Noble Gases

A family of six chemically stable and unreactive nonmetals in Group 18 whose outer electron shells contain the maximum allowed number of valence electrons.

Physical Property

A characteristic of a substance that can be observed or measured without altering the chemical identity of the substance.

Chemical Property

A characteristic of a substance that can only be observed when it undergoes a reaction that produces one or more new substances.

Density

A physical property defined as the ratio of mass to volume, calculated via the formula $\text{Density} = \frac{\text{Mass}}{\text{Volume}}$.

Physical Change

A change in the physical properties or state of a substance that does not alter its underlying chemical identity and is generally reversible.

Chemical Change

A process in which one or more substances are irreversibly transformed into chemically distinct new substances.

Bohr-Rutherford Diagram

An atomic model depicting the protons and neutrons inside the central nucleus and the electrons arranged in surrounding orbital shells.

Electron Shell Limits

The maximum number of electrons permitted in each energy level of a Bohr-Rutherford model: 2 in Shell 1, 8 in Shell 2, 18 in Shell 3, and 32 in Shell 4.

Isotope

Two or more forms of the same chemical element possessing identical numbers of protons but differing numbers of neutrons.

Ion

An atom or group of bonded atoms that carries an electrical charge due to the gain of electrons (anion) or loss of electrons (cation).

Electronic Waste (E-Waste)

Discarded electronic products that constitute only $2\%$ of total landfill waste yet represent the number one source of toxic heavy metals such as lead, mercury, and lithium in landfills.