Types of Chemical Reactions

Types of Chemical Reactions

Classification of Chemical ReactionsChemical reactions can be classified in one of two ways:Based on how atoms are reorderedBased on how energy/ heat is transferred

Vs.1. Synthesis Reaction(Marriage)Two or more elements/compounds combine to form a single product. General equation: A + B AB 2Mg + O2 2MgO

+ABAB

Example: SynthesisBurning Magnesium2Mg + O2 2MgO(white powder) A + B AB

Synthesis Reaction is

Synthesis Reaction is8 Fe + S8 8 FeS

Synthesis Celebrity Style!!+

2. Decomposition Reaction(The Break-up)A single reactant/compound, breaks into two or more parts. General equation: ABA + B 2H2O2 2H2O + O2

+BABA

Example: DecompositionHydrogen peroxide on a cut2H2O2 2H2O +O2 AB A + BBubbles are O2Liquid is water.Elephants toothpaste

Decomposition Reaction is

MgO2 Mg + O2Decomposition Reaction is

+Decomposition Celebrity Style!!+

3. Single Replacement ReactionA more reactive Single element replaces a less reactive element in a compound. (metal replaces another metal a non-metal replaces a non-metal)

The general equation: A + BC AC + B

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(Rico Suave Scandal)ABBCACExample: Single ReplacementAluminum and Copper (II) ChlorideAl + CuCl2 AlCl3 + CuA + BC BA + C

Example: Single ReplacementMagnesium and Hydrochloric acidMg + 2HCl MgCl2 + H2A + BC BA + C

What do you know about Hydrogen gas!?Predicting the Products!!Mg + HCl _____ + _____

If a metal will only replace a metal, and a non-metal will only replace a non-metal then what will the products be??Mg kicks out H so that Mg can bond with Cl.BUT WAIT!!! H is the leader of the NOF 7 group so its diatomic!BUT WAIT!!! Is it balanced??

MgClH22 2 2 Lets Try to Predict a few! Mg + AlCl3 ________ + __________ Cl2 + NaBr ________ + __________ Copper(II) + silver nitrate yields _____+ _______ _________ + _______MgCl2AlNaClBr2Cu Ag(NO3) Cu(NO3)2AgWhat type of Reaction is Single Replacement

What type of Reaction is Single Replacement++Single Replacement Celebrity Style!!

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4. Double Replacement ReactionTwo compounds switch partners to form two new compoundsGeneral equation: AB + CD AD + CB KI+ Pb(NO3)2 KNO3 + PbI

Note: Metals replace metals and non-metals replace non-metals

++Scandal of Scandals!!ABCBCDAD

Example: Double ReplacementPotassium Iodide and Lead (II) NitrateKI(aq) + Pb(NO3)2(aq) KNO3(aq) + PbI(s) AB + CD AD + CB

Predicting the Products!!MgCl + Ca(SO4) _____ + ________

If a metal will only replace a metal, and a non-metal will only replace a non-metal then what will the products be??Mg kicks out Ca so that Mg can bond with SO4.BUT WAIT!!! Make sure CaCl has the right formula. (Ca2+ Cl 1-)BUT WAIT!!! Is it balanced??

CaCl2MgSO42What type of Reaction is Double Replacement++What type of Reaction is Double Replacement

Double Replacement Reaction (NO3)2 + I

KPb Pb(NO3)2 + K I KNO3 + PbI2 Double Replacement Celebrity Style!! ( We remade the ending)+

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5. Combustion ReactionA hydrocarbon or alcohol is reacted with oxygen gas to always form the products carbon dioxide and water.

General equation:Hydrocarbon + O2 CO2+ H2O or Alcohol

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CHExample: CombustionBurning Methane (Natural Gas)CH4 + O2 CO2 + H2OWhat type of Reaction isC10H8 + 12 O2 ---> 10 CO2 + 4 H2O

CombustionHint: Look for CO2 and H2O as products!! Where have you heard Combustion before??6. Neutralization ReactionsUnfortunately we cannot forget about neutralization reactions (a.k.a. acid-base reactions)! Acid and a base react to form a salt and water. General equation: HX + MOH MX +H2O HCl + NaOH NaCl + H2O

Where M is a metal and X is a non-metal

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What type of Reaction isHBr + NaOH ---> NaBr + H2O

Neutralization1. Classifying based on energy transfer

Endothermic vs. Exothermic(how energy/heat is transferred)EXOTHERMIC (exo= outside)- energy is released as a product during a chemical reaction given off as heat (hot rxn!!)H2O2 O2 + H2O + Heat (heat is a product)

ENDOTHERMIC (endo= inside)- energy is required (a reactant) during a chemical reaction and heat is absorbed (cold rxn!!)2NH4 + H2O + Heat 2NH4(OH) (heat is a reactant)

Endothermic Reaction:The Cold packNaCH3COO + H2O + Heat 2NH4(OH)

BrrrSodium acetate in water