Boron, with an atomic number of 5, has two stable isotopes: boron-11 (11B) and boron-10 (10B). The atomic number indicates the number of protons in the nucleus of an atom, which for boron is always 5.
For both isotopes:
- Protons: Since the atomic number is 5, both 11B and 10B have 5 protons.
Now, let’s look at neutrons:
- Neutrons in 11B: The notation 11B indicates a mass number of 11. To find the number of neutrons, we subtract the number of protons from the mass number: 11 – 5 = 6 neutrons.
- Neutrons in 10B: Similarly, for 10B, with a mass number of 10, we do the same calculation: 10 – 5 = 5 neutrons.
Finally, let’s consider electrons:
- Electrons: In a neutral atom, the number of electrons equals the number of protons. Therefore, both 11B and 10B will have 5 electrons.
In summary:
- 11B: 5 protons, 6 neutrons, 5 electrons
- 10B: 5 protons, 5 neutrons, 5 electrons