Chemical Reaction Review

Balance this equation, Ca + H₂O --> CaO + H₂

• Ca + 2H₂O --> CaO + 2H₂
• 2Ca + H₂O --> CaO + H₂
• Its balanced as it is
• Cannot be balanced

What type of chemical reaction is this one?
Al(OH)₃ --> Al2O3  + H2O

• Decomposition
• Combustion
• Synthesis
• Single Replacement 

What type of chemical reaction is this one?
CUO + CO2 --> CuCO3

• Decomposition
• Combustion
• Synthesis
• Single Replacement 

What type of chemical reaction is this one?
Ca + MgCl2 --> CaCl2 + Mg

• Decomposition
• Combustion
• Synthesis
• Single Replacement 

What is a coefficient?

• The small number on the right of the chemical symbol.
• The large number to the left of a formula.

Why must chemical equations be balanced?

• So that the equation doesn't explode

• The reaction won't happen until it is balanced

• Based on the Law of Conservation of Matter, matter cannot be created or destroyed.

• Based on the Law of Conservation of Energy, energy cannot be created or destroyed.e

What type of reaction is illustrated below?
2HI --> H₂  +  I₂

• synthesis
• decomposition
• single replacement
• double replacement

What type of reaction is illustrated below?

Zn + H₂S --> ZnS + H₂

• synthesis

• decomposition

• single replacement

• double replacement

What type of chemical reaction is this one?
C₂H₂ + O₂ --> CO₂ + H₂O

• Decomposition
• Combustion
• Synthesis
• Single Replacement 

Evidence of a chemical reaction include:

• Phase change
• No new substance
• Bubbles forming
• Shape change