Final answer:
The neutral atom that is isoelectronic with Sn^4+ is Krypton (Kr), which has the same electron configuration [Kr] when Sn loses four electrons to form the Sn^4+ ion.
Step-by-step explanation:
The student has asked about a neutral atom that is isoelectronic with Sn4+.
To find such an atom, we need to consider the electronic configuration of a Sn4+ ion. Tin (Sn) has the ground state electron configuration of [Kr]5s24d105p2.
When tin forms a 4+ ion, it loses four electrons to become [Kr]5s04d105p0.
This configuration is isoelectronic with krypton (Kr), a noble gas with the electron configuration 1s22s22p63s23p63d104s24p6.
Thus, the neutral atom that is isoelectronic with Sn4+ is Krypton (Kr).