Electron Capture Equation In Details

 Electron capture occur when a proton in an atom capture an inner electron forming a neutron and a neutrino, the neutrino is ejected out of the atom,

 One thing about an electron capture equation is that the other the particle is on the left hand side unlike other decays

¹²⁸₅₆Ba + ⁰_-1e → ¹²⁵₅₇Cs + ⁰₀.

²⁶₁₃Al + ⁰_-1e → ²⁶₁₂Cs + ⁰₀v

⁵⁹₂₈Ni + ⁰_-1e → ⁵⁹₂₇Co + ⁰₀v

⁴⁰₁₉K + ⁰_-1e → ⁴⁰₁₈Ar + ⁰₀v

Examine the following equations

 You will observe that the electron ⁰_-1e is on the left hand side unlike beta and positron decays where electrons or positrons are on the right side respectively.

  The atomic number decreased by one while the atomic mas remain unchanged.