Answer
The element is radium (Ra), and it has 142 neutrons within its nucleus.
Work Step by Step
If the ion has a 2+ charge, that means that there are fewer electrons than there are protons. If the ion has 86 electrons, that means it has 88 protons for the net charge to be +2. The number of protons is the same as the atomic number; therefore, the element that corresponds to atomic number 88 is radium (Ra).
We find the number of neutrons in this ion by subtracting the number of protons (88) from the mass number (230); thus, there are 142 neutrons in this ion.