Chemistry
Chapter 10
Notes #1
Covalent Compounds -Review
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Common Diatomic molecules
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Acids – Binary and Oxy
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Hydrogen (gas), Oxygen, Nitrogen, Fluorine,
Chlorine, Bromine, Iodine
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

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Example Fluorine becomes Fluoride
Example: CO2 - Carbon Dioxide
 Example: N2O4 – dinitrogen tetraoxide
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Ionic Compounds - Review
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Cation + Anion (positive + negative)
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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.
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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
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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

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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 Reactions
Exothermic
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
 Word Equation

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Isooctane + oxygen
Products
-> carbon dioxide + water
Skeleton Equation

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->
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
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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