Chemistry

Chapter 10Notes #1

Covalent Compounds -Review Common Diatomic molecules

Hydrogen (gas), Oxygen, Nitrogen, Fluorine, Chlorine, Bromine, Iodine

Acids – Binary and Oxy Hydrochloric, Hydrosulfuric, Sulfuric, Sulfurous,

Chlorous Regular Compounds

Carbon Dioxide, Carbon tetrachloride, diphosphorus pentoxide

Covalent Compounds Nonmetal + nonmetal Use prefixes to tell how many of each (find

it on the pink sheet) 2nd element, change the ending to –ide

Example Fluorine becomes Fluoride

Example: CO2 - Carbon Dioxide

Example: N2O4 – dinitrogen tetraoxide

Ionic Compounds - Review Cation + Anion (positive + negative)

Charges matter!!!!!! Roman numerals tell charge for transitions Polyatomics don’t end in –ide (mostly) Need your cheat sheet

Examples Tin (IV) oxide, lead (II) sulfite, strontium

carbonate, aluminum oxide, magnesium chloride, calcium oxide, potassium iodide, potassium iodate

Ionic Compounds Metal + nonmetal Find charge on periodic table for elements,

on pink sheet for polyatomics Ions come together to balance charge NO charges (superscripts) in the formulas,

just subscripts EX: Mg2+ and Cl- = MgCl2 Name: Name the metal, change the

nonmetal ending to –ide EX: MgCl2 = Magnesium Chloride

Chemical Reactions- Review Change in the composition and properties

of a substance, or substances, as the result of a chemical reaction. Ex. Souring of Milk Ex. Rusting of iron Ex. Change in color Burning./Combustion

Chemical reactions change substances

Chemical Reactions- Review Signs of Chemical Change

Combustion (Flame, Smoke, Ash) New substance formed

Color change Precipitate (solid formed when mixing 2 liquids)

Bubbling/fizzing (Production of a gas) Change in Temp (warmer or cooler) Disappearance of a metal Formation of liquid droplets Odor

Reactions Breaking bonds require energy Forming bonds releases energy 2 terms for describing the overall energy

transfer in a chemical reaction Exothermic Endothermic Reactions

Chemical Reactions Exothermic Reactions

Chemical reactions that overall release energy They use energy to break bonds, but more

energy is released in the formation of the products than was used to break the bonds

•Endothermic Reactions•Chemical reactions that overall use energy

•They use more energy to break bonds than is released in the formation of the products

Chemical ReactionsExothermic Endothermic

Chemical Reactions Original bonds are broken Atoms rearrange New bonds form

Reactants: starting substances that will undergo a chemical change

Product: substance that is the result of a chemical change/reaction

Chemical Reactions Energy is conserved in chemical reactions

Law of conservation of energy Chemical energy – energy stored in the

bonds of the compounds Total energy on the reactant side of an

equation equals the total energy on the product side

This includes the energy given off….

Chemical Reactions Reactants -> Products Word Equation

Isooctane + oxygen -> carbon dioxide + water

Skeleton Equation C8H18 + O2 -> CO2 + H2O

Chemical Equation 2C8H18 + 25O2 -> 16CO2 + 18H2O

Chemical Reactions In a balanced chemical equation energy

and mass is conserved You can only change coefficients

NO CHANGING SUBCRIPTS! Changing the subscripts changes the

chemicals, therefore it changes the entire reaction

Changing coefficients is just changing the amounts of chemicals necessary to carry out the reaction