Process control, represents a fundamental part of chemical engineering and is based on the maintenance of optimal conditions within the process through adjustment of certain process variables. Processes are most often controlled within reactors, distillation columns, heat exchangers etc. Most commonly controlled process variables in those processes are temperature, flow, pressure and level. Within a control loop, the actions of measurement, comparison and adjustment of process variables take place. This bachelor thesis is based on the explanation of measurement, which is carried out by using measuring instruments/devices. One of the most commonly measured process variables in industry and laboratories is temperature. It can be defined as a measure of heat of a certain object, or more precisely, as a measure of average kinetic energy of particle movement, and it represents one of the basic physical quantities. In order to measure temperature, changes in pressure, volume, electrical conductivity and other physical values which are proportional to temperature can be used. Measuring instruments for determining temperature can generally be divided into dilatation thermometers, pyrometers and electric thermometers. The selection of a particular measuring instrument depends on the process factors and the characteristics of the measuring transducer. In this bachelor thesis, the goal was to choose a suitable measuring transducer for the measurement of fluid temperature and wall temperature of a batch reactor, while being guided by the process factors and characteristics of the measuring transducers. It was shown that, for measuring temperature in a batch reactor, electric thermometers are most suitable.