To calculate the molar mass, we need to add the atomic masses of each atom in the compound. Lead (Pb) has an atomic mass of 207.2 g/mol, nitrogen (N) has an atomic mass of 14.01 g/mol, and oxygen (O) has an atomic mass of 16.00 g/mol.

There is one lead atom, two nitrogen atoms, and six oxygen atoms in Pb(NO3)2. So, the molar mass can be calculated as follows:

Molar mass of Pb(NO3)2 = (1 × 207.2 g/mol) + (2 × 14.01 g/mol) + (6 × 16.00 g/mol)

= 207.2 g/mol + 28.02 g/mol + 96.00 g/mol

= 331.22 g/mol

Therefore, the molar mass of Pb(NO3)2 is 331.20 g/mol.