Chemical Equations Reactants Products

Chemical Reaction Reactants  Products chemical reaction Reactants is the process by which one or more substances change into one or more new substances. Reactants the original substances in a chemical reaction. Products the substances that are created in a chemical reaction. Reactants  Products

Chemical Reaction Versus Physical Change chemical change new substance forms with properties that differ from original substance physical change changes of state of matter

A chemical equation vs Word Equation methane + oxygen  carbon dioxide + water --------------------------------------------- Chemical Equation ?CH4 + ?O2  ?CO2 + ?H2O

Equations and Reaction Information (s) Solid (l) Liquid (g) Gas (aq) Aqueous (dissolved in water)  Yields Reversible reactions Clip

Balancing Equations Conservation of mass The amount and type of atoms starting a reaction must be the same as the amount and type of atoms after the reaction

Balancing Equations coefficient multiplies the number of atoms of each element in the formula that follows. H2O: 2 hydrogen atoms, 1 oxygen atom 2H2O: 4 hydrogen atoms, 2 oxygen atoms

Diatomic Elements Elements that when found free in nature are 2 atoms bonded together H2, N2, O2, F2, Cl2, Br2, and I2 Can have other subscripts when in compounds but not when alone

H2O + CO2 -----> C6H12O6 + O2 Na + NaNO3 ---> Na2O + N2

Assignment Practice Problems Pgs 269 271 273