Chemistry Semester 2 Study Guide-Terms

Electrolyte
an ionic compound whose aqueos solution conducts an electric current.

Formula unit
the simplest ratio of ions represented in an ionic compound.

Aqueous solution
a solution in which the solvent is water.

Chemical equation
a statement using chemical formulas to describe the identities and relative amounts of the reactants and products involved in the chemical reaction.

Chemical reaction
the process by which the atoms of one or more substances are rearranged to form different substances.

Coeffecient
in a chemical equation, the number written in front of react or product tells the smallest number of particles of the substance involved in the reaction.

Combustion reaction
a chemical reaction that occurs when a substance reacts with oxygen, releasing energy in the compounds.

Coplete ionic equation
an ionic equation that shows all the particles in a solution as they realistically exist.

Decomposition reaction
a chemical reaction that occurs when a single compound breads down into two or more elements or new compounds.

Double-replacement reaction
a chemical reaction that involves the exchange of positive ions into two or more elements or new compounds.

Ionic bond
the elctrostatic force that holds oppositely charge particles together in an ionic compound.

Alloy
a mixture of elements that has metallic properties.

Anion
an ion that has a negative charge.

Cation
an ion that has a positive charge.

Chemical bond
the force that holds two atoms together and formces an attraction of a positive ion for a negative ion or by the attraction of positive nucleus for negative electrons.

Monatomic ion
an ion formed from only one atom.

Oxidation number
the positive or negative charge of a monatomic ion.

Oxyanion
a polyatomic ion composed of an element, usually a nonmetal, bonded to one or more oxygen atom.

Polyatomic ion
an ion made up of two or more atoms bonded together that acts as a single unit with a net charge.

Precipitate
a solid produced during a chemical reaction in a solution.

Product
a substance formed during a chemical reaction.

Single-replacement reaction
a chemical reaction that occurs when the atoms of one element replace the atoms of another element in a compound.

Sigma bond
a single coalent bond that’s formed when an electron pair is shared by the direct overlap of bonding orbitals.

Polar covalent bond
a type of bond that’s formed when electrons are not shared equally.

Resonance
condition that occurs when more than one valid Lewis structure exists for the same molecule.

Endothermic
chemical reaction in which a greater amount of energy is required to break te existing bonds in the reactants than is released when the new bonds form in the product molecules.

Exothermic
chemical reaction in which two or more substances react to yield a single product.

Solute
a substance dissolved in solutions.

Solvent
the substance that dissolves a salute to form solutions.

Structural Formula
a molecular model that uses symbols and bonds to show relative positions of atoms.

Molecule
forms when two or more atoms covalently bond and are lower in potential energy than its constituent’s atoms.

VSEPR model
Valence Shell Electron Pair Repulsion model

Coordinate covalent bond
forms when one atom donates a pair electrons to be shared with an atom or ion that needs two elctrons to become stable.

Hybridization
process by which the valence electrons of an atom are rearranged to form four new identical orbitals.

Oxyacid
any acid that contains hydrogen and an oxyanion.

Electronegativity
indicates the relative ability of elements atoms to attract electrons in a chemical bond.