NT Chapter 2—Matter and Change Classifying Matter States of Matter • Solid o ___________________ shape and volume o Particles tightly ___________________ together o Expands when ___________________ o Incompressible • Liquid o __________________ in shape o Takes the shape of the bottom of a ________________________ o _____________________________ o Expands when heated • Gas o Particles can __________________ freely in all __________________________ o _____________________ to fill container o Take the shape of the container o Particles are ____________ apart o Easily compressed o Gas vs. Vapor § Gas—substance in the gaseous state at room ___________________________ • Example: Oxygen § Vapor—gaseous state of a substance that is _______________ or _________________ at room temperature • Example: Water vapor Classification of Matter • Substance—matter that has a ________________________ composition and distinct properties o Element—substance that ___________________ be separated into simpler substances § Most occur _______________________ on Earth; 118 elements to date § Example: gold, carbon, hydrogen **First letter in ALL chemical symbols are ALWAYS capitalize, second letter is ALWAYS lowercase •
o Compound—__________ or more elements _____________________ combined in fixed proportions § Example: water § Has properties ______________________ than its components • Example: solid sodium + chlorine gas = table salt § Can be separated by only by _____________________ means § Formula of a compound (subscripts denote ____________________ of atoms) • Mg3N2 and Mg3(PO4)2 • _____ Mg, _____N and ______ Mg, ______ P, _______ O • Numbers outside of _____________________________ get multiplied in Mixture—combination of two or more pure _________________________ in which each pure substance _________________ its individual chemical identities 1 o Homogeneous—composition of the mixture is the _______________ throughout § Also called a ___________________ § Mixed at the ____________________________ level and has a ___________________ phase • solid-­‐solid (metal alloy, brass) • liquid-­‐liquid • Gas-­‐gas o Heterogeneous—does not have uniform _________________________ and the individual substances remain _____________________ § Example: salad, trail mix o Do not have fixed ______________________ o Can be created or separated by ____________________ means § Dissolving—homogeneous solid-­‐liquid mixture where the liquid phase is retained § Distillation—separates homogeneous ___________________-­‐__________________ mixtures using differences in ______________________ points § Filtration—separates ______________________________ solid-­‐liquid mixtures § Chromatography—separates ___________________________ liquid-­‐liquid mixtures based on differences in _________________________ and tendency to ____________________ across the surface of another material § Crystallization—separates homogeneous ________________-­‐____________________ mixtures; results in a pure _________________ substance § Evaporation—allowing a solution (solid dissolved in a liquid) to “___________”; typically the liquid ___________________________ into the air § Decant—to pour a liquid, from one container to another, gently to not disturb the sediment Properties and Changes in Matter Properties of Matter • Physical property—can be _______________________ or viewed without _____________________ the sample’s composition § Example: density, color, odor, state of matter, boiling point, melting pint, shape o Extensive property—properties that ___________________ on the amount of substance present § Example: volume, mass o Intensive property—properties are __________________________ of the amount of substance present § Can be used to _________________________ a substance § Example: density, boiling point, temperature • Chemical property—how a substance _________________________ with another substance o Example: iron can react with oxygen, carbon dioxide is not flammable Changes in Matter • Physical—alter a substance ________________________ changing the composition o Example: bend, grind, crumple, split, phase changes • Chemical o Process in which a substance(s) is ______________________ into one or more _________ substances o Example: combust, ferment, burn, rot, tarnish o Also known as a chemical ____________________________ § Chemical equation—use of _______________________ to represent a chemical reaction • Example: CH4 + O2 → CO2 + H2O § Reactants 2 • ______________________ substances • Found on the ______________ hand side of a chemical equation • Reactants from example above are _____________ and ______________ § Products • Substances _____________________ • Found on the ______________ hand side of a chemical equation • Products from example above are _____________ and _____________ o Law of conservation of mass—mass is neither ______________________ or _____________________ during a chemical reaction § Mass of the ___________________ = mass of the _________________________ o Signs a chemical reaction has occurred § Bubbling (__________ production) § ______________ change § Precipitate forms (____________ formation) § _____________________ change (temperature change) § The only way to know for sure is to check the composition before and after!!! 3