The Mass of an Atom with 843 Protons, 843 Electrons, and 992 Neutrons
When determining the mass of an atom, we focus on the contributions from protons, neutrons, and electrons. While electrons do have mass, it is so small that it has little effect on the overall mass of the atom. For simplicity, we can primarily calculate the mass based on protons and neutrons, as they account for nearly all of the atom’s mass.
1. Understanding the Components
- Protons: These positively charged particles reside in the nucleus of the atom. The mass of a proton is approximately 1.0073 atomic mass units (amu).
- Neutrons: Neutrons are electrically neutral particles that also reside in the nucleus. The mass of a neutron is slightly larger than that of a proton, about 1.0087 amu.
- Electrons: Electrons are negatively charged particles that orbit the nucleus. The mass of an electron is approximately 0.00055 amu, which is negligible compared to protons and neutrons.
2. Calculating the Atomic Mass
Given:
- 843 protons
- 843 electrons (Mass of electrons is negligible)
- 992 neutrons
The total mass of the atom (in amu) can be calculated by summing the contributions from the protons and neutrons.
Mass of protons=843 protons×1.0073 amu=849.1449 amu\text{Mass of protons} = 843 \, \text{protons} \times 1.0073 \, \text{amu} = 849.1449 \, \text{amu} Mass of neutrons=992 neutrons×1.0087 amu=999.6184 amu\text{Mass of neutrons} = 992 \, \text{neutrons} \times 1.0087 \, \text{amu} = 999.6184 \, \text{amu} Total mass=849.1449 amu+999.6184 amu=1848.7633 amu\text{Total mass} = 849.1449 \, \text{amu} + 999.6184 \, \text{amu} = 1848.7633 \, \text{amu}
3. Final Mass of the Atom
The mass of the atom, based on the given number of protons, neutrons, and electrons, is approximately 1848.76 amu.
4. Conclusion
Although electrons contribute a very tiny mass, their effect is almost negligible in this calculation. Therefore, the mass of an atom with 843 protons, 843 electrons, and 992 neutrons is approximately 1848.76 amu.
