That sounds like hydrogen!
Hydrogen
The most abundent isotope of Hydrogen has only a proton for a nucleus with a single electron orbiting it. However some isotopes of Hydrogen do have neutrons in the nucleus.
Isotopes of a element are simply versions of that same element with different count of neutron, with that in mind they take all of the isotopes of a specific element and average them together taking in account the percent abundance of each so the most common isotope is the one on the periodic table.
Fluorine.
1s22s22p5
Hydrogen
silicon
By weight or by number of atoms? By number of atoms
The isotopes 252Cf and 251Cf.
The earthworm
Tin or Stannum with 10 stable isotopes
The most abundent isotope of Hydrogen has only a proton for a nucleus with a single electron orbiting it. However some isotopes of Hydrogen do have neutrons in the nucleus.
It has 10
Isotopes of a element are simply versions of that same element with different count of neutron, with that in mind they take all of the isotopes of a specific element and average them together taking in account the percent abundance of each so the most common isotope is the one on the periodic table.
The known weighted-averagemass of all the naturally occurring* isotopes for an element is the atomic mass of the element.____________________*This is not the same as "all the known isotopes", becausemost elements have known isotopes that are not naturally occurring.
No. The most common isotope(s) of an element are often stable.
Chemical reactions involve electrons - not protons or neutrons. All isotopes of the same element have an identical number of electrons (just the number of neutrons differs) and hence the chemical properties are identical/very similar.