eng Science and Education Publishing World Journal of Chemical Education 2375-1657 2021-11-28 9 4 136 143 10.12691/wjce-9-4-6 WJCE2021946 article Matthias Ducci ducci@ph-karlsruhe.de 1 Department of Chemistry, University of Education Karlsruhe, Karlsruhe, Germany Diazotype is a historical light tracing process which was used, in particular, for reproducing technical drawings. This paper first explains the principle of the diazotype. Thereafter, a researching and developing teaching concept with a varity of newly developed experiments is presented for chemistry lessons at secondary level II. http://pubs.sciepub.com/wjce/9/4/6/wjce-9-4-6.pdf diazonium salt photolysis azo dye fluorescence diazotype