Mass of adsorbent/conc. of Cr (III) ion	30˚C	40˚C	50˚C	60˚C
Mass of adsorbent/conc. of Cr (III) ion	ΔS (kJ/mol/K)
1 g, 0.1 M	−0.04	−0.04	−0.04	−0.038
1.5 g, 0.1 M	−0.042	−0.041	−0.042	−0.042
2 g, 0.1 M	−0.042	−0.041	−0.041	−0.041
1 g, 0.2 M	−0.022	−0.022	−0.022	−0.022
1.5 g, 0.2 M	−0.025	−0.025	−0.025	−0.025
2 g, 0.2 M	−0.024	−0.024	−0.024	−0.024
1 g, 0.3 M	−0.015	−0.015	−0.015	−0.015
1.5 g, 0.3 M	−0.016	−0.017	−0.017	−0.016
2 g, 0.3 M	−0.016	−0.016	−0.016	−0.016