Răspuns:
MNaOH =ANa+AO+AH=23+16+1=40
MHgO=AHg +AO=201+16=217
MFe(OH)2=,AFe+2×AO+2×AH=56+2×16+2×1=90
MCH4 =AC+4×AH=12+4×1=16
MCuSO4 =ACu+AS+4×AO=64+32+4×16=160
MK2CO3=2×AK+AC+3×AO=2×39+12+3×16=138
MNH3=AN+3×AH=14+3×1=17
MMgCl2 =AMg +2×ACl=24+2×35,5=95