By Ollie Auerbach

A chemical Reaction

A process in which atoms of the same or different elements rearrange themselves to form a new substance. While they do so, they either absorb heat or give it off

http://www.weldonryan.com/images/chemical_reaction_final.png

http://dictionary.reference.com/browse/chemical%20reaction

Chemical Reaction Basics

What is happening during a chemical reaction?

Reactants react to form products.

Reactants- the materials that exist before the chemical reaction

Products- substances that are created by the chemical reaction

Atoms are only rearranged. No new atoms are created.

What part of atoms are affected by chemical reactions?

A chemical reaction involves the motion of electrons in the forming and breaking of chemical bonds.

http://en.wikipedia.org/wiki/Chemical_reaction

Signs of a chemical reaction

Bubbling Change in temperature Light is emitted Change in color Energy is produced A gas is produced A precipitate forms ( chemical reaction that

forms a solid powder from two liquid substances)

http://images.encarta.msn.com/xrefmedia/sharemed/targets/images/pho/t046/T046403A.jpg

http://antoine.frostburg.edu/chem/senese/101/reactions/symptoms.shtml

In a chemical reaction, matter is neither gained or lost Or more simply put, the mass of substances produced

(products) by a chemical reaction is always equal to the mass of the reacting substances (reactants).

http://www.mi.mun.ca/users/edurnfor/1100/atomic%20structure/tsld004.htm

http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-L/law_conservation_of_mass.html

http://www.tea.state.tx.us/student.assessment/resources/online/2006/grade10/science/images/40graphicaa.gif

Energy in Chemical Reactions

Chemical reactions always involve a change in energy. Energy is neither created or destroyed. Energy is absorbed or released in chemical reactions. Chemical reactions can be described as endothermic or exothermic reactions.

http://www.usoe.k12.ut.us/curr/science/sciber00/8th/matter/sciber/chemtype.htm

http://www.beaconhurst.stirling.sch.uk/departments/science/chem7.jpg

Exothermic/ Endothermic Reactions Exothermic Endothermic Energy is released The energy released was

originally stored in the chemical bonds of the reactants.

Any reaction that involves combustion (burning) is an exothermic chemical reaction.

Often the heat given off causes the product(s) to feel hot

Ex. – Dissolving ammonia chloride into water,

Ex. - 2H2+O2 changes to 2H2O

http://www.usoe.k12.ut.us/curr/science/sciber00/8th/matter/sciber/chemtype.htm

Energy is absorbed Energy is required for

reaction to happen Energy absorbed is

usually electrical energy or heat energy

Ex. –Photosynthesis, sunlight + 6CO2(g) + H2O(l) =

C6H12O6(aq) + 6O2(g)

Activation Energy

Energy that must be overcome for a chemical reaction to occur

The energy often needed to initiate a certain process

http://chemistry.twu.edu/tutorial/activation-energy.gif

http://www.bio-medicine.org/biology-definition/Activation_energy/

http://en.wikipedia.org/wiki/Activation_energy

Chemical Potential Energy

Energy that is stored and can be transformed into other forms of energy Sound Heat Electricity Light

http://www.chemistryland.com/CHM107/Energy/HydrogenElectronNoSpring.jpg

Combustion

The act or process of burning O2 will always be a reactant in a combustion reaction When something burns it is almost always a combustion

reaction Combustion reactions are almost always exothermic (Give

off heat) An example- the combustion of hydrogen and

oxygen, which is a commonly used reaction in rocket engines:

2H2 + O2 → 2H2O(g) + heat. The result is water vapor.

http://en.wikipedia.org/wiki/Combustion

http://www.iun.edu/~cpanhd/C101webnotes/chemical%20reactions/combustion.html

http://www.ueberbill.com/images/ROCKET.jpg

Decomposition

The state of being reduced into original elements. (breaking down, disintegration)

Opposite of combination reactions Compound decomposes (splits up)

Basic formula- AB ---> A + B

An example- Water broken down into hydrogen and oxygen 2H2O → 2H2 + O2

http://en.wikipedia.org/wiki/Chemical_decomposition

Synthesis

The combining of separate elements or substances to form a whole.

Basic Formula- A + B ---> AB Examples-

2Na + Cl2 → 2 NaCl (formation of table salt) 4 Fe + 3 O2 → 2 Fe2O3 (iron rusting)

http://en.wikipedia.org/wiki/Chemical_synthesis

http://www.dearbornschools.org/schools/dcmst/staff/whittaker/NaCl123.gif

Single Displacement

Double Displacement Cations and Anions of two different

molecules switch places two form to totally different compounds.

Basic Formula- AB + CD ---> AD + CB An example- The reaction of lead

nitrate with potassium iodide to form lead iodide and potassium nitrate Pb(NO3)2 + 2 KI ---> PbI2 + 2 KNO3

http://www.hempfieldarea.k12.pa.us/webdir/MILLERS/dd%20reaction.png

http://misterguch.brinkster.net/6typesofchemicalrxn.html

Bibliography

“Chemical Reaction Definition-” http://dictionary.reference.com/browse/chemical%20reaction

“Chemical Reactions” http://en.wikipedia.org/wiki/Chemical_reaction

“Ten Signs of a Chemical Change” http://antoine.frostburg.edu/chem/senese/101/reactions/symptoms.shtml

“The Law of Conservation Mass” http://www.mi.mun.ca/users/edurnfor/1100/atomic%20structure/tsld004.htm

“Law of Conservation Mass- Definition”

http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-L/law_conservation_of_mass.html “Types of Chemical Reactions”

http://www.usoe.k12.ut.us/curr/science/sciber00/8th/matter/sciber/chemtype.htm

“Activation Energy” http://www.bio-medicine.org/biology-definition/Activation_energy/

http://en.wikipedia.org/wiki/Activation_energy

“Combustion” http://en.wikipedia.org/wiki/Combustion

“Combustion Reactions” http://www.iun.edu/~cpanhd/C101webnotes/chemical%20reactions/combustion.html

Bibliography Continued

“Chemical Decomposition” http://en.wikipedia.org/wiki/Chemical_decomposition

“Chemical Synthesis” http://en.wikipedia.org/wiki/Chemical_synthesis

“The Six Types of Chemical Reactions” http://misterguch.brinkster.net/6typesofchemicalrxn.html

Chemical Reaction Power Point

By Ollie Auerbach

http://www.chemistryland.com/CHM130/IconChemicalReactions.jpg