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Methyl ammonium aluminum alum


Phase change data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Eugene S. Domalski and Elizabeth D. Hearing

Temperature of phase transition

Ttrs (K) Initial Phase Final Phase Reference Comment
176.18crystaline, IIcrystaline, IAshworth and Steeple, 1968S = 9.70 J/mol*K 90 K Anomaly: Schottky type anomaly between 65 and 120 K, maximum at 90 K, entropy estimated to be between 6 and 9 J/mol*K. 176 K Anomaly: Due to free rotation of methylammonium group (CH3NH3); observed entropy change at 176.18 K is 9.70 J/mol*K.

References

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Ashworth and Steeple, 1968
Ashworth, T.; Steeple, H., The continuous heating method of calorimetry and its application to the study of low temperature specific heat anomalies in methyl-ammonium alum, Cryogenics, 1968, 8, 225-234. [all data]


Notes

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