1s2 2x2 2p6 3s2 3p6 is the electron configuration ofr for which ion?

Question

I believe your 2x2 should be 2s2. You have 18 electrons in filled orbitals. That could be a +1 charged element 19 (K+) or a +2 charged element 20 (Ca++) \, for example. In either case, it is a very stable ion because of the filed orbitals.