Chemical Reactions

Michelangelo La Mattina

What is chemical reaction?• Chemical reaction tells you the substances

present before and after the reactions.• Reactants – substances that undergo change• Products – new substances formed as a result

of that change• The law of conservation of mass states that

mass is neither created nor destroyed in a chemical reaction.

• Should be balanced because the masses are equal, law conservation of mass

Chemical Equation• Reactants Products• Ex.

– C + O CO2

– Carbon + Oxygen Carbon Dioxide • Chemical Equation is a representation of a chemical reaction in which the reactants and products are expressed as formulas.

• The way it is read – “Carbon and oxygen react and form carbon dioxide” or “The reaction of carbon and oxygen yields carbon dioxide.

Classifying Reactions

• Synthesis Reactions

• Decomposition Reactions

• Single Displacement

• Double Displacement

Synthesis reactions

• Reaction in which two or more substances react to form a single substance

• Ex. A + B AB• 2Na + Cl2 2NaCl

• Eggs + Brownie mixture + water + oil Brownies

Decomposition

• Opposite of Synthesis reaction• Compound breaks down into two or

more simpler substances• AB A + B• Ex. 2H2O 2H2 + O2

• Candle Wick + Wax

Single Displacement• Reaction in which one element takes

the place of another element in a compound

• A + BC B + AC• Ex. Cu + 2AgNO3 2Ag + Cu(NO3)2

»Pepperoni + Cheese pizza Cheese + Pepperoni Pizza

Double Displacement

• Two different compounds exchange positive ions and form two new compounds

• AB + CD AD + CB• Ex. Pb(NO3)2 + 2KI PbI2 + 2KNO3

• French fries and ketchup + Hamburger and soda French fries and soda Hamburger and Ketchup

Where I Got My Info

Science Textbook Pages 192 - 204

Song In PowerPoint

• Howard Jones - And Do You Feel Scared

BACKGROUNDS CITED

• httpyorkcountyschools.orgteachersjchristmanchemistry.jpg• httpwww.flickr.comphotostheshyfox299678392sizeso

The End