Studies of heats of reactions of binary liquid mixtures are given a
considerable importance in understanding the nature of molecular interactions.
Such studies mainly help to know the enthalpies of liquid mixtures. The present
study deals with design of a simple embedded based system for measuring heat
of mixing of binary liquid mixtures. The system consists of two units, cell
assembly and data acquisition system. One of the components of the binary
mixture is taken into the cell, other component is injected in to the cell through
appropriate mechanical arrangement. The reaction on mixing causes the
thermal changes which are sensed by the thermal sensor, that can be measured
up to 10-4oC. The entire unit is interfaced to LPC 2366 ARM based controller (A
less power consumption device made by philips). The ARM controller sends the
data to the Personal Computer through the serial port and software is developed
to calculate enthalpy values. A comparison of the results obtained with the
literature data showed good agreement. The designed system can be used as an
alternative for the measuring heats of mixing of binary liquid mixtures. The
paper deals with the design aspects both hardware and software features of the
Keywords - liquids, mixtures, ARM Processor, embedded
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