Chemical Equations and Reactions

• • Indicators of a Chemical Change: colour change, change in temperature, bubbling/fizziness, precipitate
• • Law of Conservation of Mass:  
  • Matter cannot be created or destroyed in a chemical reaction. It is rearranged
  • The total pass of reactants MUST equal the total mass of the products
  • All chemical reactions must be balanced due to the Law of Conservation of Mass
• • Combustion reaction: hydrocarbon + oxygen → H2O + CO2
• • Incomplete combustion: not enough oxygen, produces monoxide
• • complete combustion: enough oxygen
• • Activity series: used to determine whether a single displacement reaction will occur or if there is no reaction  a single displacement reaction will not occur if one of the reactants is lower than the other on the reactivity series
• • Physical properties vs Chemical properties
  • Physical: colour, density, hardness, melting/boiling points
  • Chemical: the ability to undergo chemical change