I. Chemical Equations A. Reactants: the starting materials (on the left of the arrow) B. Products: the ending materials (on the right of the arrow) C. Physical States: (s) = solid or (ppt) precipitate (l) = liquid (g) = gas (aq) = aqueous (solution in water) D. Coefficients: numbers in front of a compound that tell you how many moles of the compound you have 1. Example: 2 NaBr + Ca(OH) 2  CaBr NaOH A chemical rxn is simply a chemical change. Products have different properties than reactants.

Conservation of Matter Matter is neither created nor destroyed in a chemical reaction. The number and type of elements on one side must always be on the other side. They can be rearranged but the same number and type MUST BE on both sides. This is why Chemical Equations Must Be Balanced

II.Types of Chemical Reactions Combustion: An Exothermic reaction of a hydrocarbon with oxygen to form water and carbon dioxide 1. Basic Form: C x H y + O 2  H 2 O + CO 2 2. Example: C 2 H 5 OH + 3 O 2 (g)  3 H 2 O (l) + 2 CO 2 (g) +  + O O O O OO O O O O C C H H H H H H H H HH HH C C O O O O

II. Types of Chemical Reactions Synthesis: the combining of two or more substances at least one product is larger than the reactants. Polymerization: a type of synthesis that produces long chain products. Eg. Nylon (Polyamide or Dacron (Polyester) 1. Basic Form: A + B  AB 2. Example: 2 Mg + O 2  2 MgO + → O O O Mg O

II. Types of Chemical Reactions Decomposition: when one substance breaks down into 2 or more simpler substances (the opposite of synthesis) 1. Basic Form: AB  A + B 2. Example: 2 H 2 O (l)  2 H 2 (g) + O 2 (g)  + O O H H H O H O H H H H

II. Types of Chemical Reactions Single Displacement/Replacement: when a single element replaces an element in a compound creating one new compound and displaces the other element 1. Basic Form: A + BC  AC + B 2. Example: Fe (s) + CuSO 4 (aq)  FeSO 4(aq) + Cu (s) +  + SO 4 Fe Cu

II. Types of Chemical Reactions Double Replacement/Displacement: two elements from two different compounds switch places to form two new compounds 1. Basic Form: AB + CD  AD + BC 2. Example: 2 AgNO 3 (aq) + BaCl 2 (aq)  2 AgCl (aq) + Ba(NO 3 ) 2 (aq) +  + NO 3 Ag Ba Cl

III. Practice 1. 2 NaBr + Ca(OH) 2  CaBr NaOH 2. 2 NH 3 + H 2 SO 4  (NH 4 ) 2 SO 4 3. C 5 H 9 O + O 2  CO 2 + H 2 O 4. 3 Pb + 2 H 3 PO 4  3 H 2 + Pb 3 (PO 4 ) 2 5. Li 3 N + 3 NH 4 NO 3  3 LiNO 3 + (NH 4 ) 3 N 6. 3 HBr + Al(OH) 3  3 H 2 O + AlBr 3