AP Chem Unit 4 Review

Physical Change

changes affecting the form of a chemical substance, but not its chemical composition
alterations in size, shape or state

Chemical Change

a change that produces matter with a different composition than the original matter

Indicators of a chemical change

Change in Temperature.
Change in Color.
Noticeable Odor (after reaction has begun)
Formation of a Precipitate.
Formation of Bubbles.

Reactants

A starting material in a chemical reaction

Products

The elements or compounds produced by a chemical reaction.

Dissolving

The process of mixing a solute in a solvent to produce a homogeneous mixture

Synthesis reaction

a reaction in which two or more substances combine to form a new compound

Decomposition

A chemical reaction that breaks down compounds into simpler products.

Single Displacement

one element trades places with another element in a compound: A + BC --> AC + B

Double Displacement

AB + CD --> AD + CB

Combustion

A fuel with oxygen to create water and CO2

Law of Conservation of Matter

Matter is not created nor destroyed in any chemical or physical change

Compounds

2 or more elements chemically combined

Elements

A molecule composed of one kind of atom; cannot be broken into simpler units by chemical reactions.

Particulate Diagram

a box in which colored balls are drawn to represent atoms, molecules or compounds

Solid

A form of matter that has a definite shape and volume

Liquid

A state of matter that has no definite shape but has a definite volume.

Gas

A state of matter with no definite shape or volume

Aqueous Solution

a solution in which water is the solvent

Precipitate

A solid that forms from a solution during a chemical reaction.

Solubility Rules

All Group 1, ammonium, and nitrate salts are always soluble

Spectator Ions

Ions that do not take part in a chemical reaction and are found in solution both before and after the reaction

Net Ionic Equations

ionic equations that include only the particles that participate in the reaction

Complete Ionic Equations

ionic equations that show all of the particles in a solution as they actually exist

Limiting Reactants

The reactant in a chemical reaction that limits the amount of product that can be formed.

In an equation, one reactant will be in excess and one will be the limiting reactant.

This is calculated using moles.

Theoretical Yield

the maximum amount of product that can be produced from a given amount of reactant

Titration

a measured amount of a solution of unknown concentration is added to a known volume of a second solution until the reaction between them is just complete

Acid Base Titration

a laboratory procedure in which a basic (or acidic) solution of unknown concentration is reacted with an acidic (or basic) solution of known concentration, in order to determine the concentration of the unknown

Redox Titration

a specific method used to determine the concentration of an unknown solution using reducible titrants or titrands, typically by measuring voltage changes.

Precipitation Titration

a titration in which the concentration of an ion is determined by precipitating it with another ion

Acid Base Reactions

a proton donor (acid) transfers a proton to a proton acceptor (base)

Strong acids…

come apart easier and form weaker acids in acid-base rxns

Acid vs Base

acid has a Ph lower than 7 and a base has a higher Ph than 7. Acids release H+ ions into solution and bases remove H+ ions by combining with OH-

Amphiprotic

A species that can either accept or donate a proton.

Redox

A combination of reduction and oxidation reactions.

Oxidation

loss of electrons

Reduction

gain of electrons