Phosphoric Acid (H3PO4) H3O4P1(cr) T(K) Cp S -[G-H(Tr)]/T H-H(Tr) delta-f H delta-f G log Kf 0 0. 0. INFINITE -16.980 -1265.927 -1265.927 INFINITE 100 42.844 34.528 183.578 -14.905 -1275.048 -1226.961 640.899 200 75.856 74.598 119.270 -8.935 -1281.203 -1176.480 307.265 298.15 106.064 110.544 110.544 0. -1284.375 -1124.314 196.975 300 106.608 111.202 110.546 0.197 -1284.411 -1123.321 195.588 315.500 111.303 116.688 110.713 1.885 CRYSTAL <--> LIQUID 400 136.900 146.019 115.089 12.372 1285.789 1069.271 139.633 500 167.193 179.822 124.668 27.577 -1283.719 -1015.323 106.070 600 197.485 212.982 136.631 45.811 -1278.830 -962.056 83.754 700 227.777 245.700 149.880 67.074 -1271.116 -909.831 67.892 800 258.069 278.092 163.885 91.366 -1260.559 -858.906 56.081 900 288.361 310.238 178.363 118.688 -1247.143 -809.475 46.981 1000 318.653 342.187 193.149 149.038 -1230.854 -761.692 39.787