Device comprising a tool holder and a removably attachable tool

A device for use with two or more reaction vessels, the device comprising:

• a tool holder, which can be displaced in an x direction and a z direction which is perpendicular to the x direction;
• a first tool in the form of at least two dispensers, that are individually displaceable in the z direction by first motive means of the first tool, the distance between the at least two dispensers can be adjusted by a further motive means of the first tool, and that, when the device is used in combination with two or more of the reaction vessels, are spaced away from each other a distance that is generally equal to a distance that separates the at least two reaction vessels;
• at least one further tool that is adapted to be removably secured to the tool holder as an alternative to the first tool, and
• a controller, the first and at least one further tool being arranged with respect to the controller so that the controller can automatically cause the first tool to be removed from the tool holder and thereafter automatically cause the at least one further tool to be removably secured to the tool holder, the automatic changeover from the first tool to the at least one further tool allowing for (i) the performance or preparation of a chemical reaction in a reaction vessel or (ii) the mixture of chemicals.