Heat Capacities and Densities of Some Liquid Chloro-, Bromo-, and Bromochloro-Substituted Benzenes

The heat capacities at constant pressure and densities of chlorobenzene (ClBz), bromobenzene (BrBz), 1,2-dichlorobenzene (1,2-DClBz), 1,3-dichlorobenzene (1,3-DClBz), 1,2-dibromobenzene (1,2-DBrBz), 1,3-dibromobenzene (1,3-DBrBz), 2-bromochlorobenzene (1,2-BrClBz), and 3-bromochlorobenzene (1,3-BrClBz) were measured within the temperature range from (283.15 to 353.15) K. The heat capacities of four other compounds [1,4-dichlorobenzene (1,4-DClBz), 1,2,3-trichlorobenzene (1,2,3-TClBz), 1,2,4-trichlorobenzene (1,2,4-TClBz), and 1,2,3,4-tetrachlorobenzene (1,2,3,4-TClBz)] were also measured between their melting point and 353.15 K. All measurements were performed by means of DSCIII (Setaram) differential scanning calorimeter. Assuming that the molar heat capacity shows an additive character, a simple equation was proposed that allows one to predict C p values of liquid chloro and bromo derivatives of benzene as a function of temperature with an accuracy below 1 %. Densities of some of the investigated compounds were measured with the use of a DMA 5000 automatic densitometer.