There's growing evidence ...Fentanyl (or hydromorphone) have a better side effect profile than morphine (remember the vaunted vasodilation is only a side effect) thereby making fentanyl a better choice..
The subatomic particles in the nucleus of a carbon atom are protons and neutrons. The atomic nucleus contains protons and usually neutrons (except for hydrogen-1 (protium) atoms. The number of protons is an element's atomic number and is the same for all atoms of an element. Carbon has atomic number #6#. So all atoms of carbon have #6# protons in their atomic nuclei.
An electron is a subatomic particle that has a negative charge of -1 and is located in the volume of atoms around the nucleus (so not in the nucleus itself) Electrons have no known components or substructure and are therefore generally considered to be elementary particles.