Giải thích các bước giải:
\(M_{Fe{Cl_3}} = 56 + 35,5.3= 162,5\ \text{g/mol}\)
\(M_{{Fe_3}{O_4}}=56.3 +16.3=232\ \text{g/mol}\)
\(M_{Ca_3(PO_4)_2}=40\cdot 3+2\cdot (31+16\cdot 4)=310\ \text{g/mol}\)
\(M_{K_2Cr_2O_7}=39.2 + 52.2+16.7 =294\ \text{g/mol}\)
\(M_{Cr(OH)_3}=52 + 3(16+1)=103\ \text{g/mol}\)
\(M_{NaHCO_3}=23+1+12+16.3=84\ \text{g/mol}\)