what happens to the mass number and atomic number when it undergoes beta decay

what happens to the mass number and atomic number when it undergoes beta decay

 when an atom under a beta decay, it atomic number changes while its mass number remain constant. it can be explained as follows.

 the following occur depending on either it a beta minus or beta plus decay.

  in a beta minus decay, a neutron in the decaying atom split into a protons , an electrons and an electron antineutrino.  the atomic number of the atom increases by one while the mass number remain constant. the  atom(element) raise one position in the periodic table of elements. let us observe the decay of radioactive carbon-14 into nitrogen.

₆C¹⁴ = ₇N¹⁴ + β

atomic number increases from 6 to 7 because proton is “gained”.

in  the beta plus decay or positron decay, a proton split into a neutron, positron and an electron neutrino.  the atomic number decreases by one  while the mass number remain constant. hence nuclear transmutation occur.

let us look at the decay of radioactive magnesium-23 into nitrogen,

₁₂Mg²³ = ₁₁Na²³ + β

the atomic number change from 12 to 11, because there is “loss” of proton.