- a process where one or more substances (elements) rearrange themselves to form a new substance.

 What part of atoms are affected? In a chemical reaction the electrons are affected by forming and breaking chemical bonds.  What is happening during a chemical Rx? 1. Reactants react to form products. reactants - the materials that are their before the reaction products - the substances that are formed from the reaction 2. Substances that are formed from the reaction fitch.wikispaces.com/Chemical+Reaction+Primer

 Bubbling  Increase or decrease in temperature  Light  Change in Color  Energy Produced  Gas Formed  Formation of Precipitate (precipitate - a liquid added to a liquid, forming a solid which is the precipitate) s.htm&usg=__3hHoM5XfiXPEqQ9kJMC8UktYZoc=&h=288&w=364&sz=17&hl=en&start=16&um=1&tbnid=AgaL_6Rr0U793M:&tbnh=96&tbnw=121&prev=/images%3Fq%3Dche mical%2Bdecomposition%2Breaction%26gbv%3D2%26um%3D1%26hl%3Den

 The Law of Conservation of Mass – “The principle that in any closed system subjected to no external forces, the mass is constant irrespective of its changes in form; the principle that matter cannot be created or destroyed.”  In other words matter can be rearranged but not destroyed or created.

 Chemical reactions are changes that result in one or more new substances.  These changes always have a change in energy.  This means that when a chemical reaction occurs energy is either given off or taken in.  Energy reactions can be described as endothermic and exothermic reactions.

 Exothermic - a chemical reaction that releases heat  Releases energy in the form of heat, light and electricity  EX- Rusting Iron 8/7.JPG examples.shtml  Endothermic – a chemical reaction that absorbs heat  Gains energy in the form of heat  Need heat to be performed  EX - Cooking an egg Endothermic reaction of barium hydroxide and ammonium salt

 Potential Energy – energy that is stored and can be transformed into other forms of energy such as heat, light, electricity and sound

 Energy that is needed to initiate the reaction

 Synthesis  Decomposition  Combustion  Single Replacement  Double Replacement

 When two or more substances combine to form a more intricate compound.  The opposite of Decomposition  Basic formula - A +B  AB  Example - Hydrogen Gas + Oxygen Gas = Water  Formula -

 The process of burning – the production of heat and light  It is an exothermic reaction  Example - CH 4 + 2O N 2 → CO 2 + 2H 2 O N 2 + heat The flames are caused from the fuel that is going through combustion (burning).

 A single, uncombined element replaces another element in a compound  Basic Formula - A+BC  AC+B  Example – When Zinc combines with Hydrochloric Acid, the Hydrogen is replaced by Zinc.  Formula Visual Single Replacement 

 A compound that is broken up into two different products. (two at the least)  The opposite of Synthesis  Basic Formula - AB  A + B  Example - Water broken down into hydrogen gas and oxygen gas  Formula –

 Two compounds swap places in order to form two new compounds  Basic Formula – AB + CD  AD + CB  Example – When Silver Nitrate combines with Sodium Chloride, Silver Chloride and Sodium Nitrate are formed because the Silver and Sodium swap places.  Formula –  Visual Double Replacement

Chemical Reaction Definition – Chemical Reaction Basics – Signs of a Chemical Reaction – The Law of Conservation of Mass – Chemical Potential Energy – Endo and Exothermic Reactions –

Activation Energy – Synthesis Reaction – Combustion Reaction – Single Replacement Reaction – Decomposition Reaction- Double Replacement Reaction –