Which element has 47 electrons?
If we assume that the atom is neutral, then the element is Silver (Ag).
If we assume that the atom of our mystery element is neutral, then the number of electrons is equal to the number of protons. The number of protons is the atomic number, which being 47 identifies this element as Silver (Ag).
However, if we allow for charged atoms, in other words ions, then the answer is not definite. If we look at the neighbours of silver in the periodic table:
We can see that if we reduce the number of electrons of a cadmium atom by one we have an ion with 47 electrons:
Similarly we can have: