Physical Science S2 Exam Study Guide - States and Properties of Matter, Atomic Structure, Periodic Table

Flashcards for Physical Science S2 Exam Review

State of Matter

A distinct form that matter can take, commonly solid, liquid, gas, and plasma.

Kinetic Theory of Matter

Theory stating that all matter is made of constantly moving particles.

Phase Change

A transition of matter from one state to another (e.g., melting, freezing, vaporization, condensation, sublimation, deposition).

Endothermic Change

A process that absorbs heat from its surroundings.

Exothermic Change

A process that releases heat to its surroundings.

Heat of Fusion

The amount of heat required to change a substance from a solid to a liquid at its melting point.

Heat of Vaporization

The amount of heat required to change a substance from a liquid to a gas at its boiling point.

Chemical Properties

Characteristics of a substance that determine how it will react with other substances (e.g., flammability, reactivity with acid).

Chemical Change

A change that results in the formation of new substances; indicated by color change, gas production, precipitate formation, or heat change.

Pure Substance

A substance with a fixed chemical composition and distinct properties (e.g., element, compound).

Mixture

A combination of two or more substances that are physically combined.

Solution

A homogeneous mixture where one substance is dissolved evenly throughout another.

Suspension

A heterogeneous mixture with large particles that settle out over time.

Colloid

A heterogeneous mixture with intermediate-sized particles that do not settle out.

Density

Mass per unit volume of a substance. Common units are g/cm³ or kg/m³.

Physical Change

A change that affects the form or appearance of a substance but does not change its chemical composition (e.g., cutting, melting).

Density Formula

Density = Mass / Volume (ρ = m/V)

Element

A pure substance consisting only of atoms that have the same number of protons in their nuclei.

Compound

A substance formed when two or more chemical elements are chemically bonded together.

Atom

The basic building block of matter.

Atomic Theory

A theory that states all matter is composed of atoms.

Subatomic Particles

Protons, Neutrons, and Electrons.

Proton Charge and Location

Positive (+1), located in the nucleus.

Neutron Charge and Location

Neutral (0), located in the nucleus.

Electron Charge and Location

Negative (-1), located in energy levels/orbitals around the nucleus.

Atomic Mass

The total number of protons and neutrons in an atom's nucleus.

Atomic Number

The number of protons in an atom's nucleus, which determines the element's identity.

Valence Electrons

Electrons in the outermost energy level of an atom; they determine the chemical properties of the element.

Periodic Table Organization

Arranged in order of increasing atomic number.

What is an ion

Charged atom

Ionic bond

Transfer of electrons (metal + nonmetal)

Covalent bonds

Sharing electrons (nonmetal + nonmetal)

Polar molecule

Uneven charge

N=N

triple bond between two nitrogen atoms

Naming

Ionic: Name metal + nonmetal with -ide

Covalent: use prefixes(mono-, di-, etc.)

Oxidation

Loses electrons

Reduction

Gaines electrons

Signs

Color change, temp change, bubbles, light, precipitate

Law of conservation of matter

Matter cannot be created or destroyed