Answer:
The molar mass of Pb(Cr2O7)2 is 639.2 g/mol.
639 g
Explanation:
Pb(Cr₂O₇)₂
Molar mass of each element:
Pb = 207
Cr = 52
O = 16
now solve:
207 + ( 52 * 2 + 16 * 7 ) * 2
207 + ( 216 ) * 2
207 + 432
