Krypton - 16-12-2003 at 08:07
To 20 ml of 96% H2SO4 add slowly 30ml of 90 % HNO3
and than 20 g of benzoic acid. Stirr the mixture for 2 hours
at 80 C and than 1 hour for 95 C. Let cool the mixture and
than add slowly 2 litre of destilled water and let stand at 5 C
for 2 hours, filter out the green-yellow crystals.