Răspuns:
a)
MHNO3=1+14+3×16=63g/mol
n=m/M=18,9/63= calculeaza
b)
MaCa(OH)2=40+2×16+2×1=74g/mol
n=m/M=14,8/74= calculeaza
c)
MN2=2×14=28g/mol
n=m/M=0,42/28= calculeaza
d)
MH2SO4=2×1+32+4×16=98g/mol
n=m/M=0,147/98= calculeaza
e)
MH2O=2×1+16=18 g/mol
n=m/M=48,6/18= calculeaza
f)
MO2=2×16=32g/mol
n=m/M=192/32= calculeaza
Explicație: