2 ElementsPure _________; can’t be broken down simpler substances by _________ meansare arranged in order _________(# of p+) on the Periodic Tableeach made of one type of _________Look around the room for some!Aluminum (Al), Argon (Ar), Zinc (Zn), Nitrogen (N), Carbon (C), Gold (Au)
3 Hydrogen is the simplest element and makes up over 90% of all matter our universe!
4 CompoundsPure substance composed of atoms of two or more _____________Ex. water (H2O), ________________, table salt (NaCl)_____________________ by physical means; can only be separated by chemical meansHeld together by ______________(ionic, covalent, metallic, etc.)
5 Why form compounds?Atoms like to be stable and happy; they want full _________________Some atoms have full shells and are already happy being alone (__________- He, Ar, Ne, etc.)___________don’t have full shells- they fill their shells by combining with other types of atoms Na +1 + Cl -1 NaCl
6 Molecule The ______________________that can exist Some examples: Water H2OCarbon monoxide COHydrochloric acid HCl
7 How do compounds combine and/or break down? By a chemical reaction (substance is changed into something else)- this causes a chemical change in the substanceEx. Hydrogen and Oxygen combine to form water 2H2 + O2 2H2OAnother example is rust:4Fe + 3O2 2Fe2O3
8 MixturesCombo of two or more substances; not pure; are ________ but not ___________combinedMay be separated by _______means- evaporation, filtration, magnets, picking out pieces, etc.Exist in any phase- liquids (ethanol & gas); liquid/gas (Coke®); solids (taco salad); gas/solid (smoke)
10 Homogeneous mixture -have a __________________________ A.K.A. solutions ex. saltwater, bronze, air,mixed ___________particles are ___________distributed
11 Physical changesPhysical change- may involve a change in state (ex. solid to liquid), or change in size, shapeExamples of physical changes are filtering, evaporation, ripping paper, melting, dissolvingThe makeup of the object is unchanged (ex. ripped paper is still paper)
12 Chemical ChangesChemical change- new substance is formed; products are different from the reactantsEx. of chemical changes are: burning, dissolving w/ acid, rusting, passing an electrical current through something
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