Fe+S -> FeS ( si mai ramane si Fe in exces)
[tex]M_{ FeS_{2} }= 56+32=88 g/mol[/tex]
Pe reactie avem 14/56=x/88 => x=22 g pirita se obtin
FeS(s) + 2 HCl(aq) = FeCl2(aq) + H2S(gaz)
Fe+2HCl ->FeCl2+ H2
MH2S=2+32=34 g/mol
Punem cantitatile pe reactie:
22/88=y/34 => y=34/4=8.5 grame gaz H2S
n=V/Vm=m/M => 8.5/34=z/22.4 => z=3,6 L H2S se degaja in conditii normale