Europium has two stable isotopes, ¹⁵¹Eu and ¹⁵³Eu. ¹⁵¹Eu has a mass of 150.9199 amu and ¹⁵³Eu has a mass of 152.9212 amu. What are the abundances of ¹⁵¹Eu and ¹⁵³Eu?
¹⁵¹Eu ¹⁵³Eu
(A) 32.75% 67.25%
(B) 47.81% 52.19%
(C) 75.31% 24.69%
(D) 39.92% 60.08%