pV= mRT/M
1,05x340= 852x0,082x(273+90) / M---> M = 71g/mol---> Cl2
n= 852kg / 71kg/kmol= 12kmol
1molCl2.........N,A molecule.............2N,A atomi
12000...............x................................y
calculeaza x, y ,inlocuind numarul lui Avogadro N,A= 6,023X10²³