| Name of Element | Element Symbol | Mass Number | Atomic Number | Protons | Neutrons | Electrons |

Question

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

Answer 1

To complete the table for the element Lead (Pb) with a mass number of 207, we can use the following information:

1. Atomic Number (Z): The atomic number of Lead is 82. This means it has 82 protons.
2. Protons: Since the atomic number is the same as the number of protons, Lead has 82 protons.
3. Neutrons: The number of neutrons can be calculated by subtracting the atomic number from the mass number: \[ \text{Neutrons} = \text{Mass Number} - \text{Atomic Number} = 207 - 82 = 125 \]
4. Electrons: In a neutral atom, the number of electrons equals the number of protons, so Lead has 82 electrons.

Now, we can fill in the missing information in the table:

| Name of Element | Element Symbol | Mass Number | Atomic Number | Protons | Neutrons | Electrons | |------------------|----------------|-------------|---------------|---------|----------|-----------| | Lead | Pb | 207 | 82 | 82 | 125 | 82 |