Molar mass of NiCO3 = Atomic mass of Ni + Atomic mass of C + 3$AtomicmassofO$

The atomic mass of Ni = 58.69 g/mol
The atomic mass of C = 12.01 g/mol
The atomic mass of O = 16.00 g/mol

Molar mass of NiCO3 = 58.69 + 12.01 + 3$16.00$ Molar mass of NiCO3 = 58.69 + 12.01 + 48.00
Molar mass of NiCO3 = 118.70 g/mol

Therefore, the molar mass of NiCO3 is 118.70 g/mol.