Science Quiz Review - Matter, Properties, Changes, and Atomic Theory

Vocabulary flashcards covering key definitions in chemistry, physical/chemical properties and changes, safety symbols, and atomic theory history based on lecture review notes.

Matter

Anything that has mass and takes up space

Mixture

A combination of two or more substances that are not chemically combined

Pure substance

A substance in which there is only one type of particle; same composition and properties throughout

Element

A substance that contains only ONE type of atom

Compound

2 or more elements chemically combined

Heterogeneous mixture

A mixture where the substances are distinct and easily identified

Homogeneous mixture

A mixture that is the same throughout

Alloy

A mixture of two or more metals

Pictogram

Graphic elements used on a hazard label, used to identify the specific hazard class and category

Property

Properties are the characteristics that enable us to differentiate one material from another

Physical properties

Different properties of a substance that can change their state without changing identity

Examples of physical properties

Color, odor, mass, density, permeability, ductility, conductivity, melting point, boiling point, magnetism, viscosity, opacity

Chemical properties

A chemical property describes the behaviour of a substance as it changes into a new substance

Examples of chemical properties

Flammability, reactivity, toxicity, pH, surface tension

Physical vs chemical changes

PHYSICAL: simply changes the properties of a substance (size, shape, or state of matter); CHEMICAL: completely changes the composition of a substance

Physical changes examples

Tearing, crushing, phase changes

Chemical change examples

Rusting, burning something, spoiled food or baking/cooking

Protons

Positively charged particles in the nucleus of an atom

Neutrons

Neutral charged particles in the nucleus of an atom

Electrons

Negatively charged subatomic particles

Difference between WHMIS vs HHPS

WHMIS has a red, diamond border whilst HHPS has different shapes (octagon, diamond, and upside down triangle)

WHMIS symbols

Exploding bomb, flame, flame over circle, gas cylinder, corrosion, skull and crossbones, health hazard, exclamation mark, environment, biohazardous infectious materials

HHPS symbols

Poisonous, flammable, explosive and corrosive

Atomos

Indivisible

Democritus

Said that all matter is made up of tiny indivisible particles called atomos

John Dalton

Said that atoms are solid, indestructible spheres

j j thompson

Discovered the electron, plum pudding model, and chocolate chip cookie model

Robert Millikan

1909 oil drop experiment, calculated the charge of the electron, calculate the mass of electrons

Ernest Rutherford

Discovered that atoms have a tiny, heavy center called a nucleus, and that the rest of the atom is mostly empty space, gold foil experiment

Henry Moseley

used x ray spectra to determine the atomic number (positive charges)

Louis de Broglie

discovered the wave nature of electrons,proposing that all matter possesses both particle and wave-like properties.

Neils Bohr

Proposed that electrons circle the center of an atom in specific, fixed tracks like planets orbiting the sun (quantized orbit model)

Erwin Schrodinger

Quantum mechanical model, that electrons move like waves and created a mathematical equation to find where they are most likely to be around the nucleus

James Chadwick

Discovered the neutron, completed basic model of nucleus