Nitration

• How is nitrobenzene formed?

  By gently heating benzene with concentrated nitric acid and concentrated sulphuric acid (catalyst).
• What do you do I you only want one NO2 group per benzene ring?

  Keep the temperature under 55*C.
• What is the first reaction of nitration? Give the equation.

  Concentrated nitric acid and concentrated sulphuric acid react together to form the nitrating mixture. HNO3 + H2SO4 --> H2NO3+ + HSO4-
• What is the second part of nitrification? Give the equation.

  The H2NO3+ produced from the nitrating mixture gives NO2+ and H2O. H2NO3+ --> NO2+ + H2O
• What is the overall equation for nitration?

  HNO3 + H2SO4 --> NO2+ + H2O + HSO4-
• What is the electrophile in nitration?

  The nitronium ion (NO2+).
• What does the nitronium ion do after it is produced?

  Attacks the benzene ring to bond with it, which is unstable.
• What happens to stabilise the molecule after the nitronium ion bonds with it?

  The H+ ion is lost which then reacts with HSO4- to reform the catalyst.