Device having a tool holder and a tool which can be secured removeably

A device having a tool holder, comprising:

• two or more reaction vessels;
• a tool holder that can be displaced in an x direction and a z direction, the z direction being perpendicular to the x direction;
• a first tool in the form of a metering head that is adapted to be removably secured to the tool holder, the metering head being capable of dispensing into a reaction vessel a desired quantity of a first reactant or chemical component, the metering head including a housing comprising an intermediate base with a conical metering opening, and a metering shaft that can be displaced in the z direction and that includes a closure cone for partially or completely closing off the conical metering opening depending on the z position of the metering shaft;
• a second tool in the form of a material handler that is adapted to be removably secured to the tool holder as an alternative to the first tool, the material handler having at least one part that is adapted to be moved actively and independently of the tool holder so that, when the material handler is attached to the tool holder, the material handler can perform an operation that is related to (i) the performance or preparation of a reaction or (ii) the mixture of chemical components in a reaction vessel;
• a controller that is adapted to control the movement of the tool holder and of the at least one part of the second tool, the first and second tools 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 second tool to be removably secured to the tool holder;
• and
• the device further comprising a balance that is mounted on the first tool in operative relation to the first tool so that a measured quantity of a first reactant or chemical component can be dispensed into a reaction vessel.