by their mass numbers.
istopes have different numbers of neutrons and most of their elements have several istopes
deuterium and tritium.
istopes
neutrons
they have not been decided yet
istopes
Yes, they are isotopes of helium
neutrons
Examples: francium-223 or Fr-223.
Same number of protons; identical or very similar chemical properties.
Germanium has 32 protons, so for an isotope with atomic number of 70, it will have 70 - 32 = 38 neutrons in its nucleus.
The witness identified the suspect in an identity parade.We have identified the culprit.