Erik Joling Some examples from the project Microscale

Erik Joling Some examples from the project ‘Microscale experiments’ UNIVERSITEIT VAN AMSTERDAM Faculty of Science 24 May 2000 Micro. Quim 2000

Prime Directive of Microscale Chemistry Thou shalt not demonstrate 24 May 2000 Micro. Quim 2000 2

Glassware 24 May 2000 Micro. Quim 2000 3

Low-cost heating device 24 May 2000 Micro. Quim 2000 4

Chlorophyll from green leaves • methanol • green leaves 24 May 2000 Micro. Quim 2000 5

Experiments must… …be performed during a forty-five minute period …fit into the curriculum …replace the macroscale experiments in the textbook …open new perspectives 24 May 2000 Micro. Quim 2000 6

Column chromatography • aluminium oxide • mixture of potassium permanganate and potassium dichromate • 0. 5 M nitric acid • 1 M sulfuric acid 24 May 2000 Micro. Quim 2000 7

Synthesis of indigo • • • 0. 1 g 2 -nitrobenzaldehyde 0. 3 ml acetone 0. 4 ml water 2 ml 1 M sodium hydroxide 2 ml ethanol 0. 1 g sodium dithionite 24 May 2000 Micro. Quim 2000 8

Indigo STS-topic: • age-old natural dye • first synthetic dye • production by Hoechst and the decline of the Indian indigo culture 24 May 2000 Micro. Quim 2000 9

Sublimation of benzoic acid • benzoic acid • activated carbon • crunched ice 24 May 2000 Micro. Quim 2000 10

Esterification acetic acid + 1 -butanol = 1 -butyl acetate + water One reaction, three experiments: • use of a catalyst • determination of equilibrium constant • upset the equilibrium 24 May 2000 Micro. Quim 2000 11

Contact me micro@chem. uva. nl www. chem. uva. nl/chemeduc/microschaal …/Micro. Quim 2000 24 May 2000 Micro. Quim 2000 12