Colors surround us and accompany us every day and everyday steps. However, the concept of color is not as self-evident as we think. The appearance of color is associated with light and is a physical phenomenon. The color is a substance that colored other materials with special techniques. We know natural and synthetic dyes. The first is obtained from natural sources, the other is synthetically derived. Natural dyes are divided into isoprene, pyrrole, pyrimidine, pyran and quinone derivatives, synthesized on azo dyes, sulfur dyes, indigoid dyes, anthracycline and triphenylmethane dyes. Chromatography is the process of separating substances from the mixture. Different chromatographic divisions are known, depending on the interaction (absorption, distribution, ion - exchange and exclusion), looking at the mobile phase (gas, liquid) depending on the stationary phase apparatus (columnar, planar). This leads to several types of chromatography. Of which the best known are paper chromatography, thin-layer, gas and gel. As simple as a very demanding and complex process, it provides quick and effective results of the separation of the mixture. Due to the simple practical implementation, it can be used as an experiment in primary and secondary schools. With the term chromatography students meet in the 7th grade of elementary school. Research shows that learning through research is much more interesting for students and knowledge that they get more profound and lasting. A PROFILES learning module entitled "Are synthetic dyes a mixture of colorants?", Which deals with the content of natural and synthetic dyes and different methods of separating substances from the mixture, was created. The PROFILES learning module was the project of the 7th European Framework Program and is based on the teaching and teaching of natural science content based on the socio-natural context.
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