Question

What is K-electron capture?

Answer 1

K-electron capture is the capture of a `1s` electron by the nucleus of an unstable isotope.

Explanation:

Electron capture occurs when the nucleus of an unstable isotope captures an inner-orbital electron.

In the process, a proton combines with the electron and forms a neutron, and an X-ray is released in the process.

The atomic number decreases by one unit, but the mass number remains unchanged.

The captured electron usually comes from the `1s` or `2s` orbitals, because these are closest to the nucleus.

If the electron comes from the `1s` level (the K-shell), the process is called K-electron capture.

Capture from the `n=2` level is called L-electron capture, and so on.