Types of Chemical Reactions

E.Q.: What are the different types of chemical reactions and how can I predict the products?

Got that? SINGLE PRODUCT A. Synthesis Two or more substances react to produce a single product. Got that? SINGLE PRODUCT A + B  AB + 

A. Synthesis H2(g) + Cl2(g)  2 HCl(g)

2 Fe(s) + Cl2(g) → FeCl3(s) 3 2 A. Synthesis Iron and chlorine gas react to form iron(III) chloride. 2 Fe(s) + Cl2(g) → FeCl3(s) 3 2

Al(s)+ Cl2(g)  2 3 2 AlCl3(s) A. Synthesis Products: ionic – remember to cancel charges covalent - hard to tell if names are not provided Al(s)+ Cl2(g)  2 3 2 AlCl3(s)

CH4(g) + 2O2(g)  CO2(g) + 2H2O(g) B. Combustion Oxygen reacts with a substance and releases energy in the form of heat and light. O2 is always a reactant A + O2  B CH4(g) + 2O2(g)  CO2(g) + 2H2O(g)

B. Combustion 4 2 Na2O(s) Na(s)+ O2(g)  C3H8(g)+ O2(g)  5 3 4 Products: contain oxygen hydrocarbons produce CO2 + H2O Na(s)+ O2(g)  4 2 Na2O(s) Note: this reaction is also a synthesis reaction! 5 3 4 C3H8(g)+ O2(g)  CO2(g)+ H2O(g)

Carbon is burned in oxygen to form carbon dioxide gas. B. Combustion Remember: oxygen is always a reactant, and product(s) will always contain oxide. Carbon is burned in oxygen to form carbon dioxide gas. C(s) + O2(g) → CO2(g)

B. Combustion of Hydrocarbon All hydrocarbons contain carbon and hydrogen and burn in oxygen to yield the same products – carbon dioxide and water. CH4(g) + O2(g) → CO2(g) + H2O (g) 2 2

AB  A + B  + C. Decomposition Only one reactant A single compound breaks down into 2 or more simpler substances Only one reactant AB  A + B  +

C. Decomposition 2 H2O(l)  2 H2(g) + O2(g)

C. Decomposition KBr(l)  2 2 K(s) + Br2(l) Products: binary - break into elements others - hard to tell KBr(l)  2 2 K(s) + Br2(l)

C. Decomposition Decomposition often requires an energy source, such as heat, light, or electricity, to occur. For example, ammonium nitrate breaks down into dinitrogen monoxide and water when heated to a high temperature. NH4+ NO3- → N2 O + H2O NH4NO3(s) → N2O(g) + 2H2O(g)

A + BC  AC + B  + + D. Single Replacement Atoms of one element replace the atoms of another element in a compound. metal replaces metal (+) nonmetal replaces nonmetal (-) A + BC  AC + B  + +

Cu(s) + 2AgNO3(aq)  Cu(NO3)2(aq) + 2Ag(s) D. Single Replacement Cu(s) + 2AgNO3(aq)  Cu(NO3)2(aq) + 2Ag(s) Copper replaces silver

D. Single Replacement Balance this equation: Potassium replaces hydrogen; therefore, potassium must be higher (more reactive) on the activity series list than hydrogen. Balance this equation: K(s) + H2O(l) → KOH(aq) + H2(g)

D. Single Replacement Fe(s)+ CuSO4(aq)  Cu(s)+ FeSO4(aq) Products: metal  metal (+) nonmetal  nonmetal (-) free element must be more active (check activity series) Fe(s)+ CuSO4(aq)  Cu(s)+ FeSO4(aq) Br2(l)+ NaCl(aq)  N.R.

Activity Series - A metal will not always replace another metal in a replacement reaction - Different metals have different reactivities, which is the ability of a metal to react with another substance - Metals are arranged by their reactivities in an activity series - This tool helps determine if a chemical reaction will take place and determining the result of a replacement reaction

Activity Series

Activity Series: How to read it? - A specific metal can replace any metal listed below it that is in a compound - It cannot replace another listed above it The letters NR (no reaction) are usually used to show that a reaction cannot take place Ag (s) + Cu(NO3)2 (aq) NR

Activity Series Cu (s) + 2AgNO3 (aq) 2Ag(s) + Cu(NO3)2 (aq) Copper is above silver in the series, meaning it can replace silver in a replacement reaction

Activity Series Ag (s) + Cu(NO3)2 (aq) NR Silver is below copper in the series, meaning it cannot replace copper in a replacement reaction

AB + CD  AD + CB  + + E. Double Replacement ions in two compounds “change partners” cation of one compound combines with anion of the other Reactions take place in aqueous solutions AB + CD  AD + CB  + +

Pb(NO3)2(aq) + K2CrO4(aq)  PbCrO4(s) + 2KNO3(aq) E. Double Replacement Pb(NO3)2(aq) + K2CrO4(aq)  PbCrO4(s) + 2KNO3(aq)

E. Double Replacement 2 2 Pb(NO3)2(aq)+ KI(aq)  PbI2(s)+ KNO3(aq) Products: switch negative ions one product must be insoluble (check solubility table) 2 2 Pb(NO3)2(aq)+ KI(aq)  PbI2(s)+ KNO3(aq) NaNO3(aq)+ KI(aq)  N.R.

Cu(s) + 2AgNO3(aq)  Cu(NO3)2(aq) + 2Ag(s) What Type of Reactions? Pb(NO3)2(aq) + K2CrO4(aq) PbCrO4(s) + 2KNO3(aq) C(s) + O2(g) → CO2(g) Cu(s) + 2AgNO3(aq)  Cu(NO3)2(aq) + 2Ag(s)

H2(g) + Cl2(g)  2 HCl(g) 2 H2O(l)  2 H2(g) + O2(g)

Try these……. ____ NaBr + ____ Ca(OH)2  ___ CaBr2 + ____ NaOH Reaction Type : ______________________________ ____P4 + ____O2  _____P2O3 Reaction Type : _____________________ ____CaCO3  ____CaO + ____CO2 Reaction Type : _____________________

Try these……. ____ Pb + ____ H3PO4  ____ H2 + ____ Pb3(PO4)2 Reaction Type : ______________________________ ____ NH3+ ____ H2SO4  ____ (NH4)2SO4 Reaction Type : _____________________