Specific Heats of Sodium Hydroxide Solutions - ACS Publications

https://pubs.acs.org/doi/full/10.1021/ie50315a025Click to increase image size Free first page. View: PDF ... A Model for Calculating the Heat Capacity of Aqueous Solutions, with Updated Density and Viscosity Data ... The Heat of Dilution of Aqueous Sodium Hydroxide Solutions at 25°.

Correlation for temperature dependency can be found at NIST/TRC Web Thermo Tables (WTT) - NIST Standard Reference Subscription Database 3 - Professional Edition; Version 2-2012-1-Pro (subscription is required); https://wtt-pro.nist.gov/wtt-pro/index.html?cmp=zinc_hydroxide_zn~oh~2#zinc_dihydroxide/

Quoting from above signalled NIST website; it is available the «Heat capacity at saturation pressure (Crystal 1 in equilibrium with Gas) as a function of Temperature / from 13 K to 299.994 K»

Cp from other references:

For Zn(OH)2, rhomb.; Cp = 74.27 J/(mol K) at 298 K (*)

For Zn(OH)2, (s); Cp = 72.27 J/(mol K) at 298.15 K (**)

For Zn(OH)2, (c); = 74.09 J/(mol K) for 290―323 K (***)

For Zn(OH)2; for 290―364 K (****)

(*) O. Kubaschewski, C.B. Alcock, P.J. Spencer, "Materials Thermochemistry", 6th ed., Pergamon Press, 1993, p.321.

(**) http://chemister.ru/Database/properties-en.php?dbid=1&id=4200; apud: Рабинович В.А., Хавин З.Я. Краткий химический справочник. - Л.: Химия, 1977, p. 113 (1978, p. 114) [in Russian].

(***) K.K. Kelley, "Contributions to the data on theoretical metallurgy ― XIII. High-temperature heat-content, heat-capacity, and entropy data for the elements and inorganic compounds", Bulletin Bureau of Mines (U.S. Dept. of the Interior), Nº 584, Washington (D.C.), 1960, p. 207 (cf. also p. 9).

(****) P.N. Lashchenko, D.I. Kompanski, "Critical transformation points of high melting oxides and of their hydrates within the high temperature range", J. Applied Chem. [U.S.S.R.] [Zhurnal prikladnoi khimii], 8, 1935, pp. 628-653.

Zinc hydroxide has specific heat capacity of 81.2 J/mol K

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