How can we tell if a reaction takes place?

There are four clues: 1. _______________ 2. _______________ 3. _______________ 4. _______________

How can we tell if a reaction takes place? There are four clues: 1. Heat or light is given off 2. _______________ 3. _______________ 4. _______________

How can we tell if a reaction takes place? There are four clues: 1. Heat or light is given off 2. A gas is produced 3. _______________ 4. _______________

How can we tell if a reaction takes place? There are four clues: 1. Heat or light is given off 2. A gas is produced 3. A precipitate forms 4. _______________

How can we tell if a reaction takes place? There are four clues: 1. Heat or light is given off 2. A gas is produced 3. A precipitate forms 4. A change in color occurs

Type of Reactions Chemical reactions are classified into six general types Synthesis

Two or more elements or simple compounds combine to form (synthesize) one product A + B AB 2Mg + O 2 2MgO 2Na + Cl 2 2NaCl SO 3 + H 2 OH 2 SO 4

Type of Reactions Chemical reactions are classified into six general types Synthesis Decomposition

One substance is broken down (split) into two or more simpler substances. ABA + B 2HgO2Hg + O 2 2KClO 3 2KCl + 3 O 2

Types of Reactions Classify the following reactions as 1) synthesis or 2) decomposition: ___A. H 2 + Br 2 2HBr ___B. Al 2 (CO 3 ) 3 Al 2 O 3 + 3CO 2 ___C. 4 Al + 3C Al 4 C 3

Solution Classify the following reactions as 1) combination or 2) decomposition: _1_A. H 2 + Br 2 2HBr _2_B. Al 2 (CO 3 ) 3 Al 2 O 3 + 3CO 2 _1_C. 4 Al + 3C Al 4 C 3

Special Decomposition Reactions Metallic Carbonates decompose to form metallic oxides and carbon dioxide CaCO 3 CaO + CO 2 Al 2 (CO 3 ) 3 Al 2 O CO 2

Special Decomposition Reactions Metallic Hydrogen Carbonates (bicarbonates) decompose to form metallic oxides, carbon dioxide and water 2NaHCO 3 Na 2 O + H 2 O + 2CO 2 2 Al(HCO 3 ) 3 Al 2 O H 2 O + 6 CO 2

Special Decomposition Reactions Metallic Chlorates decompose into metallic chlorides and oxygen 2KClO 3 2KCl + 3O 2 Ni(ClO 3 ) 4 NiCl 4 + 6O 2

Type of Reactions Chemical reactions are classified into six general types Synthesis Decomposition Single Replacement

One element takes the place of an element in a reacting compound. A + BC AB + C Zn + 2HCl ZnCl 2 + H 2 Fe + CuSO 4 FeSO 4 +Cu 2KI + Cl 2 2KCl + I 2

Type of Reactions Chemical reactions are classified into six general types Synthesis Decomposition Single Replacement Double Replacement

Two elements in reactants take the place of each other AB + CD AD + CB AgNO 3 + NaCl AgCl + NaNO 3 ZnS + 2HCl ZnCl 2 +H 2 S

Classifying Reactions Classify the following reactions as 1) single replacement 2) double replacement __ A. 2Al + 3H 2 SO 4 Al 2 (SO 4 ) 3 + 3H 2 __B. Na 2 SO 4 + 2AgNO 3 Ag 2 SO 4 + 2NaNO 3 __C. 3C + Fe 2 O 3 2Fe + 3CO

Solution Classify the following reactions as 1) single replacement 2) double replacement 1_ A. 2Al + 3H 2 SO 4 Al 2 (SO 4 ) 3 + 3H 2 2_B. Na 2 SO 4 + 2AgNO 3 Ag 2 SO 4 + 2NaNO 3 1_C. 3C + Fe 2 O 3 2Fe + 3CO

Type of Reactions Chemical reactions are classified into six general types Synthesis Decomposition Single Replacement Double Replacement Combustion

A reaction in which a compound (most often carbon) reacts with oxygen C + O 2 CO 2 CH 4 + 2O 2 CO 2 + 2H 2 O C 3 H 8 + 5O 2 3CO 2 + 4H 2 O C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O

Type of Reactions Chemical reactions are classified into six general types Synthesis Decomposition Single Replacement Double Replacement Combustion Neutralization

A reaction in which a base (contains OH - ) reacts with an acid (contains H + ) to produce a salt and water NaOH + HClNaCl + H 2 O H 2 SO 4 + 2NaOH Na 2 SO 4 + 2H 2 O

Balancing Equations Balance the combustion equation ___C 5 H 12 + ___O 2 ___CO 2 + ___H 2 O

Solution Balance the combustion equation 1 C 5 H O 2 5 CO H 2 O