Isotopes of europium

Europium (Eu) has a number of isotopes, but the most significant ones are Europium-151 and Europium-153, which are the only naturally occurring isotopes. 1. **Europium-151 (Eu-151)**: This isotope has an atomic mass of approximately 150.9198 u and has a natural abundance of about 47.8%. It is stable and does not undergo radioactive decay.