With Pye 'Autotitration Controller', made by W G Pye and Co of Cambridge. A titration is an analyical chemical proces where in order to analyse a liquid of unknown composition, a measured quantity of it is added to measured quantities of another liquid of known composition. The experiment is stopped when a visible change of some sort is seen to occur. This is known as the 'end point' of the reaction. Traditionally, titrations would have been performed with the quantities of the known substance, or titratant, being measured and added by hand. With this apparatus, the titratant is added automatically in precise doses in response to signals received from electrodes immersed in the solution. This allows greater accuracy in determining the exact end point.
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