Science

Definitions
PURE SUBSTANCE - Atoms of only one kind; fixed physical and chemical properties
CHEMICAL FAMILY - Groups on the periodic table = alkali metals, alkaline earth metals, transition metals, halogens... etc.
MOLECULAR COMPOUND - A pure substance formed by 2 or more non-metals

Definitions
BALANCED CHEMICAL EQUATION - Both sides of chemical equation have the same amount of each element
WORD EQUATION - A chemical equation using only words and not chemical symbols
PHYSICAL PROPERTY - The physical attributes of a chemical (EX. 5 senses)

Definitions
VALANCE SHELL - The outermost shell of an element
ION - It is a charged particle that results when an atom gains or looses one or more elections
ELEMENT - A pure substance that can't be broken down into simpler substances

Definitions
PHYSICAL CHANGE - A change that occurs during a reaction to change the chemical properties of a chemical
CHEMICAL CHANGE - A change that occurs during a reaction to change the chemical properties of a chemical - these changes are irreversible

Conserving Mass
- The law of conserving matter states matter can neither be destroyed or created
- The energy from the reactants is transferred to the products, that's why they must be balanced

Reactions
SINGLE DISPLACEMENT - When a element reacts with a composition and displaces one of the element out of the compound. Metals can only displace metals, and gasses can only displace gasses
EX. 3K2SO4 + 4Al = 1Al(SO4)3 + 6K

Reactions
COMBUSTION - Two elements combine to produce a compound, water, and energy
EX. 2CuH10 + 6O2 = 8CO2 + 10H2O + Energy
ACID - An acid and a base combine to produce an ionic compound and water
EX. 1HBr + 1KO1 = 1KBr + 1H20

Elements and the Periodic Table
HALOGENS - The eighth group on the periodic table. The elements in the 17th column of the period table
NOBLE GASSES - The last group on the periodic table. The elements in the 18th column on the periodic table

Molecular Compounds
- Molecular compounds are made from 2 or more atoms sharing electrons between them to fill their valance shells
- Find the amount of electrons in the valance shell for the element and balance it with the second element
- a proofing system is used to describe how many of each element is in each molecule. If the has only one atom the "mono" prefix isn't written, but ONLY for the first element. 1 = Mono, 2 = DI, 3 = Tri, 4= Tetra, 5 = Penta, 6 = Hecta, 7 = Hepta, 8 = Octa, 9 = Nona, 10 = Deca

Ionic Compounds
- Consists of a metal and a non-metal or a group of non-metals. They contain ions (+ = Cation, - = Anion)
- In and iconic compound, the charge from the cation (+) and the anion (-) must be balanced so that the molecule is neutral. We take multiple of each to achieve neutrality
- Find the name of the ion on the periodic table using the chemical symbol. On the second element add ide, ite, or ate in exchange for the last few letters. ONLY on the SECOND element

Acids and Bases
BASES
- Contain OH-
- Taste bitter
- Bases neutralize acids
- Conduct electricity (electrolights) (non-electrolights)
- PH > 7 (Greater than 7)
- PH = Potential Hydrogen
- Indicators turn pink
- Corrosive
- Litmus indicators = pink
Phenuthaline = pink