Because their abundance is not the same.
they are known as isotopes. Dont ask people to do your homework
youm dont
An isotope is an atom of a given element with a different mass. this means it must have a different number of neutrons, as changing the amount of protons would change the element. in short, an isotope is an atom with a special number of neutrons. eg. normal hydrogen- 1 H 1 deuterium (hydrogen with a neutron) 2 H 1 if you dont understand what im talking about just wiki it.
You dont
It was then changed to "All atoms of the same element contain the same number of protons and electrons, but atoms of a given element may have different numbers of neutrons." after James Chadwick discovered that the nuclei of most atoms contain neutrons as well as protons.
When i had my 7 week scan theywere both 6.5mm. i dont know if this is average / normal.
no you get a random element and you dont change it
i dont think of myself as a girl with schizophrenia, i think of myself as nancy
you dont. if you dont know then go find out
i dont no
normal people dont. Guess your not normal.
i dont think it is. it should be "not normal" or "abnormal"