The molar mass of Pb(NO3)2, also known as lead(II) nitrate, is calculated by adding the atomic masses of all the atoms in the compound. Here’s how it’s done:
1. **Lead (Pb):** The atomic mass of lead is approximately 207.2 g/mol.
2. **Nitrogen (N):** The atomic mass of nitrogen is approximately 14.0 g/mol. Since there are two nitrogen atoms in the compound, this contributes 28.0 g/mol.
3. **Oxygen (O):** The atomic mass of oxygen is approximately 16.0 g/mol. There are six oxygen atoms in the compound, contributing 96.0 g/mol.
Adding these together: 207.2 g/mol (Pb) + 28.0 g/mol (N) + 96.0 g/mol (O) = 331.2 g/mol.
Therefore, the molar mass of Pb(NO3)2 is **331.2 g/mol**.