Reversible Reactions

Reaction arrows and reversibility

• An irreversible reaction is where reactants form products and reaction is complete
• A single headed arrow is to show that the reactants turn into products
• These reactions do not reverse
• Common reactions
  
  
• In a reversible reaction, both the forward and backward reaction can occur under the right conditions
• This type of reaction is symbolised using the double headed arrow
• Can proceed in both directions under right conditions
• Rare occurence

What is a reversible reaction

• A chemical reaction where the reactants form products that in turn, react together to reform the reactants
• A double headed arrow is used t show that a chemical reaction is reversible

Observations from hydrated copper sulphate

• Initial state - blue powder, crystal
• Heating - solid changes from blue to white, steam
• Cooling - remains white
• Adding water - white powder becomes blue, heat released

Observations from ammonia chloride

• Initial state - white powder
• Heating - white powder disappears, produces colourless gas
• Cooling - white deposits form in cooler regions of the apparatus