Combination (Synthesis) ReactionsTwo or more substances combine toform a new compound. A + X AX Reaction of elements with oxygenand sulfur Reactions of metals with Halogens Synthesis Reactions with Oxides There are others not covered here!
Decomposition ReactionsA single compound undergoes a reactionthat produces two or more simplersubstances AX A + XDecomposition of: Binary compounds H2O(l ) 2H2(g) + O2(g) Metal carbonates CaCO3(s) CaO(s) + CO2(g) Metal hydroxides Ca(OH)2(s) CaO(s) + H2O(g) Metal chlorates 2KClO3(s) 2KCl(s) + 3O2(g) Oxyacids H2CO3(aq) CO2(g) + H2O(l )
Single Replacement Reactions A + BX AX + B BX + Y BY + X Replacement of: Metals by another metal Hydrogen in water by a metal Hydrogen in an acid by a metal Halogens by more active halogens
LithiumPotassium The Activity SeriesCalcium of the MetalsSodiumMagnesiumAluminum Metals can replace otherZinc metals provided that theyChromium are above the metal thatIron they are trying to replaceNickelLeadHydrogen Metals above hydrogen canBismuth replace hydrogen in acids.CopperMercurySilver Metals from sodium upwardPlatinum can replace hydrogen in waterGold
The Activity Series of the Halogens Fluorine Halogens can replace Chlorine other halogens in Bromine compounds, provided Iodine that they are above the halogen that they are trying to replace.2NaCl(s) + F2(g) ??? 2NaF(s) + Cl2(g)MgCl2(s) + Br2(g) ??? Reaction No
Double Replacement ReactionsThe ions of two compounds exchangeplaces in an aqueous solution to formtwo new compounds. AX + BY AY + BXOne of the compounds formed isusually a precipitate, an insoluble gasthat bubbles out of solution, or amolecular compound, usually water.
Combustion Reactions A substance combines with oxygen, releasing a large amount of energy in the form of light and heat. Reactive elements combine with oxygen P4(s) + 5O2(g) P4O10(s) (This is also a synthesis reaction) The burning of natural gas, wood,gasoline C3H8(g) + 5O2(g) 3CO2(g) + 4H2O(g)