a) MNH3=17g/mol ==>n=m/M=34/17=2 moli NH3
b) MCH4=16g/mol ==> n=m/M=8/16=0.5 moli CH4
c) MHCl=36.5g/mol ==> n=m/M=73/36.5=2 moli HCl
d) MNaOH=40g/mol ==> n=m/M=120/40=3 moli NaOH
e) MHNO3=63g/mol ==> n=m/M=126/63=2 moli HNO3
f) MC6H6=78g/mol ==> n=m/M=36/78=0.461 moli C6H6