Naturally occurring europium (Eu) consists of two isotopes. One of the isotopes has a mass of 152.9212 amu and 52.19% abundance. What is the atomic mass and the mass number of the other isotopes? Give the nuclear symbol for this isotope.

Answers:

Atomic number = 63

Mass = 150.919 a. m. u

Nuclear symbol = ¹⁵¹Eu₆₃

Explanation:

Europium (Eu) is a member of lanthanide series in periodic table. these are radioactive elements that emits radiations continuously. these elements are also called rare earth element due to their rare existent.

Europium (Eu) has two naturally occurring isotopes as follow,

1) Eu¹⁵² with 52.19 % abundance.

2) Eu¹⁵¹ with 47.81 % abundance.