Atomic Mass will be 23 the new magnesium formed will be its isotope of magnesium.
We know that,
In stable condition
Number of electrons = Number of protons
Atomic number represents number of proton .
So, here number of proton is 12
Therefore, number of electron is 12
We know that -
Atomic mass = number of protons +Number of neutron
So if magnesium loses one neutron i.e. new number of neutron is 11
then its atomic mass changes.
New atomic mass will be
Atomic mass =
Atomic mass = 23
This new element with atomic mass 23 and atomic number 12 is the isotope of magnesium.
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