The aim of this experiment is to show that modern chemistry uses methods which are non-destructive in contrast to conventional ones which inevitably destroy at least part of the object. An analyser can be used for testing for example valuable jewellery which makes it a very favourable exhibit for all sexes and ages of visitors.

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   Description of the Experiment   

The analysing method used in this exhibit is "x-ray fluorescence analysis". The atoms of each element have an electron cloud characteristic of that element. When the atoms bind energy the electrons of each element will become reorganised in the atom in a manner characteristic of the element.
In this exhibit, the atoms will be excited due to radiation.

Finally, when the excited states will discharge, each element will transmit radiation characteristic of it (x-ray fluorescence). The percentages of a compound are defined by measuring the fluorescence amounts radiated by the different elements.

   Duration   

The experiment lasts about four minutes.

   Conclusion   

The analyser is able to recognise the elements of an object and to count their percentages. However, the analyser cannot tell whether the information is coming from the object or from the structure of the analyser.

If the object contains the same elements as the analyser the result will be incorrect. For this reason aluminium and lighter elements are omitted from the results. Thus you will not find, for example, the diamond in a ring among the results (diamond are made of carbon).

   Detailed Conclusion   

Let's try to understand the nature of the event step by step even though the following description is not strictly accurate.

  1. Let's imagine a stadium (an atom) where the field (the nucleus) is in the middle and surrounded by seats that lean forward. On each seat there is one big ball (the electrons). Let's imagine that the gamma quantum kicks one ball away from the lowest round of seats (shell K) and balls from the upper seats roll down to fill the empty seats one at a time.

  2. As the electrons are filling the empty places in the atom, each electron radiates a gamma quantum typical of each transfer (characteristic radiation or X-fluorescence). A part of this radiation hits the analyser.

  3. The analyser measures the energy of each gamma quantum and counts the quanta.

  4. The computer program recognises the elements and counts their percentages with the help of the analyser's information.