The cause of your abdominal bloating and back pain may depend on which symptom came first. If back pain is your primary symptom, click here to read about the causes of back pain. If your primary symptom is abdominal bloating, read on.
The yields of the most massive elements produced in bombardments of target nuclei with heavy ions become extremely small with increasing atomic number, dropping to as little as one atom per week of bombardment for elements as massive as atomic number 112.
According to HowStuffWorks, an atomic mass unit is defined as the mass of a single proton or neutron. Hydrogen, the lightest element, has an average mass of 1.00794 amu. A carbon-12 atom is made up of six protons and six neutrons, hence 12 atomic mass units. The mass of the electron is considered negligible, therefore electrons are not counted in measuring an atom's atomic mass.