Chemistry final study guide

Electron Dot Structure
the diagram that shows the bonding between atoms of a molecule and lone electrons.

Valence Electron
atom in the outermost energy level of an atom; for most atoms, it is available to be gained, lost, or shared in the formation of chemical bonds.

Octet Rule
rule that states that atoms tend to gain, lose, or share electrons so that each atom has a full outermost energy level, which is typically 8 electrons (an octet).

Ionic Bond
chemical bond resulting from the transfer of electrons from one bonding atom to another.

Metallic Bond
the chemical bond resulting from the transfer of electrons between metallic elements.

Polar Bond
the bond that has an uneven distribution of charge due to an unequal sharing of bonding atoms.

Single-Covalent Bond
chemical bond resulting from the sharing of an electron pair between two atoms.

Double Covalent Bond
chemical bond resulting from the sharing of two electron pairs between two atoms.

Triple Covalent Bond
chemical bond resulting from the sharing of 3 electron pairs between two atoms.

Structural Formula
formula that indicates how the atoms in a molecule are bonded to each other.

Cation
positive ion.

Anion
negative ion.

Monatomic Ion
ion formed from a single atom.

Polyatomic Ion
charged group of covalently bonded atoms.

Binary Ionic Compound
ionic compound consisting of two electrons.

Reactant
substance that enters into a chemical reaction.

Product
substance formed during a chemical reaction.

Coefficient
whole number that precedes a reaction or product symbol or formula in a chemical equation and indicates the relative number of representative particles involved in a reaction.

Chemical Equation
condensed statement that uses chemical formulas and identifies the reactants and products in a chemical reaction.

Balanced Chemical Equation
chemical equation that uses coefficients to show that the number of atoms of each element that enters into a reaction is equal to the number of atoms of that same element produced during the reaction (Law of Conservation of Mass).

Synthesis Reaction
the chemical reaction in which two or more simple reactants join to form a single more complex product.

Decomposition Reaction
chemical reaction in which a single complex compound is broken down into two or more products; general form is AB = A + B

Single Replacement Reaction
chemical reaction in which an uncombined element replaces an element that is part of a compound; AX + B = BX + A.

Double Replacement Reaction
chemical reaction in which atoms or ions from two different compounds replace each other; AX + BY = BX + AY.

Combustion Reaction
the chemical reaction in which an oxidant is reacted to produce heat and a new product.

Molecular Mass
the weighted average of the masses of the existing isotopes of an element.

Molar Mass
mass in grams of 1 mole of a substance.

Formula Unit
the chemical formula with the least number of elements out of the set of empirical formulas having the same proportion of ions as elements:
NaCl is the (Blank) for the ionic compound sodium chloride.

Molar Volume
volume of 1 mole of an ideal gas at standard conditions (1 atm) O degrees Celsius; Equals 22.4 L

6.02 x 10^23
quantity of a substance that has a mass in grams numerically equal to its formula mass.

Representative Particle
the smallest unit in a specific substance that naturally exists in a typical atom.

Mole
the SI unit used to measure the amount of a substance.

Avogadro’s Number
the number of representative particles in a substance present in 1 mole of that substance, and represented as 6.02 x 10^23 particles.

Standard Temp. and Pressure
0 degrees Celsius and 1 atm.

Percent Composition
the percent by mass of each element in a compound.

Limiting Reactant
the reactant that determines the amount of product that can be formed in a chemical reaction.

Excess reactant
the reactant that is not completely used during a chemical reaction.

Theoretical Yield
the maximum amount of product that could be formed from given amounts of reactants predicted by stoichiometry calculations.

Actual Yield
the amount of product produced when the reaction is carried out in a lab.

Percent Yield
is determined by dividing the actual yield by the theoretical yield and multiplying by 100.