| Atomic symbol | Atomic Number | Protons | Neutrons | Electrons | Atomic mass |

Question

|---------------|---------------|---------|----------|-----------|-------------|
| Pb | __ | __ | __ | __ | 207 |

Answer 1

To fill in the missing information for lead (Pb):

1. Atomic Symbol: Pb

2. Atomic Number: 82 (This is the number of protons and also electrons in a neutral atom)

3. Protons: 82

4. Neutrons: The atomic mass of lead is approximately 207, and since the atomic mass is the sum of protons and neutrons, we can calculate the number of neutrons as follows:

   Neutrons = Atomic mass - Protons = 207 - 82 = 125

5. Electrons: 82 (since it is neutral, the number of electrons equals the number of protons)

6. Atomic Mass: 207

Here’s the completed table:

| Atomic symbol | Atomic Number | Protons | Neutrons | Electrons | Atomic mass | |---------------|---------------|---------|----------|-----------|-------------| | Pb | 82 | 82 | 125 | 82 | 207 |