Synthesis, Combustion, and Decomposition Reactions Unit 5 Lesson 2 Synthesis, Combustion, and Decomposition Reactions Demos It is Eggothermic

Types of Reactions Synthesis Reaction Decomposition Reaction Video Link Synthesis Reaction Decomposition Reaction Single-Replacement Reaction Double-Replacement Reaction Combustion Reaction More is listed about each type on page 6 of your reference packet

A + B  AB Synthesis Reaction Examples 2 H2 + O2  2 H2O 2 or more reactants form one product. A + B  AB Examples 2 H2 + O2  2 H2O CaO + H2O  Ca(OH)2

Combustion Reaction An element or compound (generally a hydrocarbon) reacts with oxygen producing carbon dioxide, water, and heat. This is a special type of synthesis Example C2H5OH + 3 O2  2 CO2 + 3 H2O

Decomposition Reaction One reactant forms 2 or more products. AB  A + B Examples 2 HgO  2 Hg + O2 2 NaCl  2 Na + Cl2

Decomposition Binary: split apart into two elements. Ag₂O  Ag + O2 If not binary, refer to reference packet page 6 “M” means any metal Example – Metal Carbonate Na2CO3  Na2O + CO2 Example – Metal hydroxide Ca(OH)2  CaO + H2O

Copper(II) oxide  Copper + Oxygen Sample Problem 1 Copper(II) Oxide will decompose when heated strongly. Give the word and formula equation. Balance the equation Copper(II) oxide  Copper + Oxygen CuO  Cu + O2 2CuO  2Cu + O2

Sample 2 Predict the products of a synthesis reaction between Magnesium and Oxygen. Mg + O2 → MgO Balance the equation: 2Mg + O2 → 2MgO Oxygen is a diatomic! Mg2+ O2- You should not balance the equation and predict products at the same time, they are separate processes

Sample 3 What products will be formed when Al2(CO3)3 decomposes? Balance the equation AFTER predicting the products Al2(CO3)3 →???? Look at reference packet Al2(CO3)3 → Al2O3 + CO2 ___Al2(CO3)3 → ___Al2O3 + ___CO2 Al2(CO3)3 → Al2O3 + 3CO2

Sample 4 Predict the products of the following reaction: C6H14 +O2 → ????? C6H14 is a hydrocarbon reacting with O2, making this a combustion reaction. The products are water and carbon dioxide. C6H14 +O2 → H2O + CO2 __C6H14 +__O2 → __H2O + __CO2 2C6H14 +19O2 → 14H2O + 12CO2