TYPES OF REACTIONS

LAW OF CONSERVATION OF MASS Matter cannot be created nor destroyed just rearranged Chemical Equation-  Represents, with symbols and formulas, the identities and relative amounts of the reactants and products in a chemical reaction

INDICATIONS OF A CHEMICAL REACTION Production of heat, light, or temperature change Production of a gas Formation of a precipitate Color change Odor change

SYMBOLS USED IN CHEMICAL EQUATIONS NH 4 OH ( aq ) → NH 3( g ) + H 2 O ( l ) → Yields- indicates result of reaction →← Indicates reversible reaction (s) solid (l) Liquid (g) Gas (aq) Aqueous solution- dissolved in water

SYMBOLS USED IN CHEMICAL EQUATIONS ºC→ Temperature at which reaction is carried out Pressure→ Pressure exceeds normal atmospheric pressure ↑ (g) gaseous product ∆ heat → → Reactants are heated MnO 2 → Catalyst, alters rate of reaction 2H 2 O 2 (l)  2H 2 O (l) + O 2 (g) MnO 2

7 DIATOMIC COVALENT MOLECULES The 7 elements are never alone in nature and are always a molecule. All of the following are Nonpolar Covalent Br 2 - liquidBring=Bromine H 2 - gasHome=Hydrogen I 2 - solidImportant =Iodine Cl 2 - gasClass=Chlorine N 2 - gasNotes =Nitrogen O 2 - gasOr=Oxygen F 2 - gasFail=Fluorine

SYNTHESIS A + B  AB Examples: 2Mg + O 2  2MgO Sr + Br 2  SrBr 2

SYNTHESIS  + + 

DECOMPOSITION AB  A + B Examples: 2H 2 O  2H 2 + O 2 2H 2 O 2  2H 2 O + O 2 Blood Electrolysis of water- Decomposition of water using an electric current

DECOMPOSITION  +  +

SINGLE-REPLACEMENT A + BC  AC + B Examples: 2Na + 2H 2 O  2NaOH + H 2 Zn + 2HCl  ZnCl 2 + H 2 Fe + CuCl 2  Cu + FeCl 2

SINGLE-REPLACEMENT   +

DOUBLE-REPLACEMENT AB + CD  AD + CB Examples: KI + Pb(NO 3 ) 2  KNO 3 + PbI 2 AgNO 3 + NaCl  AgCl + NaNO 3

DOUBLE-REPLACEMENT They generally take place in an aqueous solution and they often produce a precipitate, gas, or a molecular compound.

COMBUSTION A combustion reaction is where a substance reacts with oxygen with the release of heat and usually the production of a flame. A hydrocarbons will react with oxygen and combust into carbon dioxide and water. C 3 H 8 (g) + 5O 2 (g)  3CO 2 (g) + 4H 2 O(g) A nonmetal will react with oxygen and combust into its nonmetal oxide and water SiH 4 + 2O 2  SiO 2 + 2H 2 O

EXAMPLE PRACTICE AlBr 3 + K  KBr + Al Single replacement

PRACTICE FeO + PdF 2  FeF 2 + PdO Double replacement

P 4 + Br 2  PBr 3 Synthesis

LiCl + Br 2  LiBr + Cl 2 Single replacement

PbBr 2 + HCl  HBr + PbCl 2 Double replacement

C 3 H 8 + 5O 2  3CO 2 + 4H 2 O Combustion

CoBr 3 + CaSO 4  CaBr 2 + Co 2 (SO 4 ) 3 Double replacement

Na 3 P + CaF 2  NaF + Ca 3 P 2 Single replacement

SrBr 2  Sr + Br 2 Decomposition

Mn + HI  H 2 + MnI 3 Single replacement

SrBr 2  Sr + Br 2 Synthesis

Li 3 PO 4 + NaBr  Na 3 PO 4 + LiBr Double replacement

CaF 2 + Li 2 SO 4  CaSO 4 + LiF Single replacement