Types of Chemical Reactions

• There are five basic types of chemical reactions:– Synthesis– Decomposition– Single Replacement– Double Replacement– Combustion

• Five Major Classes of Reactions

Synthesis Reactions

• Synthesis reactions happen when two or more substances combine to form one compound.

A + B AB

2 Na + Cl2 2 NaCl

Al + P AlP

• Magnesium and oxygen• Magnesium and Oxygen (shorter)• Iron and Sulfur• Zinc and Iodine

Decomposition Reactions

• Decomposition Reactions happen when one substance breaks down into two or more simpler substances.

• AB A + B

• CaF2 Ca + F2

• 2 Fe2O3 4 Fe + 3 O2

• Hydrogen Peroxide decomposition• Simple Elephant Toothpaste• Old foamy (Elephant Toothpaste!)• Sad Gummy Bear• Decomposition of Potassium Chlorate and Sug

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Synthesis and Decomposition

• Summary

Single Replacement Reactions

• Single Replacement reactions happen when one element is replaced by another in a compound

• A + BC AC + B

• Zn + CuCl ZnCl + Cu

• MgO + Ca Mg + CaO

• Copper (II) Chloride and Aluminum AND Copper (II) Chloride and Magnesium

• Zinc and Hydrochloric acid• Exploding Egg

Double Replacement Reactions

• Double Replacement reactions happen when two elements in a reaction exchange places with each other.

• AB + CD AD + CB

• PbCl + KBr PbBr + KCl

• HCl+Ca(OH)2H(OH)+CaCl2

• Lead Nitrate and Potassium Iodide• Precipitation Reactions

Combustion Reactions

• Combustion Reactions involve the burning (O2) of a hydrocarbon to form carbon dioxide and water.

• CXHY + O2 CO2 + H2O

• 2C2H6+7O24CO2 + 6H2O

• 2CH4 + 4O2 2CO2 + 4H2O

• Combustion of Alcohols• Fire It Up Reactions • Methane Bubbles• Budapest Combustion (long)• Plasma Bottle with Ethyl Alcohol

Water Forming (Neutralization)

• Carbon Snake• Sugar and Sulfuric Acid

Things that Affect Reaction Rate

• Some chemical reactions happen very quickly (explosions) while others occur quite slowly (rusting).

• There are five factors that can increase the rate of a chemical reaction:– Increase the temperature– Increase the concentration– Increase the surface area– Increase the pressure– Add a catalyst