The following figure shows nitrogen adsorption-desorption isotherms and pore size distributions calculated by BJH method, for bentonite (B/Na) and modified bentonite: 100 90 (a) 80 --580-110 S50-110 -520-110 B.Na 70 60 Volumen adsorbido (cm'lg), STP 50 40 30 10 0,1 0.2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 Presin relativa (PIPO) 0.0018 0.0016 (b) 0.0014 BINA 0.0012 -520-110 0.001 AVp Arp (cmlg.A 550-110 0.000 SB0-110 0.0006 0.0004 0.0002 10 100 20 30 40 50 60 70 80 90 Radio promedio de poro.r. (A) | (a) What type are the adsorption isotherms? b) What type is the porosity of the materials? (c) Are the distributions congruent with the shape of the adsorption isotherms? Explain: (d) Are the pore size distributions unimodal? Explain