About Us | Help Videos | Contact Us | Subscriptions

Members of ASA, CSSA, and SSSA: Due to system upgrades, your subscriptions in the digital library will be unavailable from May 15th to May 22nd. We apologize for any inconvenience this may cause, and thank you for your patience. If you have any questions, please call our membership department at 608-273-8080.


Institutional Subscribers: Institutional subscription access will not be interrupted for existing subscribers who have access via IP authentication, though new subscriptions or changes will not be available during the upgrade period. For questions, please email us at: queries@dl.sciencesocieties.org or call Danielle Lynch: 608-268-4976.



This article in SSSAJ

  1. Vol. 36 No. 5, p. 835-838
    Received: Dec 30, 1971
    Accepted: May 10, 1972

Request Permissions


Measurements of the Standard Entropy of Formation of Clay Minerals1

  1. Javier M. Santillan-Medrano and
  2. Hinrich L. Bohn2



The standard entropies of several clays were determined by calorimetry. The entropies of kaolinite and halloysite, 0.197 and 0.185 cal/g (50.8 and 47.7 cal/mole), respectively, compared well to literature values. The entropies of 2:1 layer-lattice aluminosilicate clay minerals were within the range of 0.15 to 0.16 cal/g. The results for the 2:1 clays are considered questionable because of the problem of low thermal conductivity of these minerals. Problems of calorimetric measurements of clay minerals are discussed.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © . Soil Science Society of America