Răspuns :
a) M H2= 2*1=2
M N2=2*14 = 28
M O2=2*16=32
M F2=2*19=38
b)M Cl2=2*35.5=71
M Br2= 2*80=160
M I2=2*127=254
M N2=2*14 = 28
M O2=2*16=32
M F2=2*19=38
b)M Cl2=2*35.5=71
M Br2= 2*80=160
M I2=2*127=254
M H2 = 1x2 = 2 g/mol
M N2 = 14x2 = 28 g/mol
M O2= 16x2= 32 g/mol
M F2 = 19x2 = 28 g/mol
M N2 = 14x2 = 28 g/mol
M O2= 16x2= 32 g/mol
M F2 = 19x2 = 28 g/mol