Identify the element associated with the configuration [Rn] 7s² 5f¹².

The electron configuration [Rn] 7s² 5f¹² corresponds to an element with a total of 102 electrons, which positions it in the actinide series of the periodic table. The [Rn] notation indicates that the electron configuration includes all the electrons up to radon, which accounts for 86 electrons. By adding the 2 electrons from the 7s² subshell and the 12 electrons from the 5f¹² subshell, we arrive at a total electron count of 100 + 2 = 102.

Californium (Cf) is atomic number 98, while Einsteinium (Es) is atomic number 99, Berkelium (Bk) is atomic number 97, and Nobelium (No) is atomic number 102. However, for the configuration in question, with 12 electrons occupying the 5f subshell, the only configuration that aligns with the Atomic number 102 is Nobelium.

Therefore, the configuration [Rn] 7s² 5f¹² indeed corresponds to Nobelium (No), not Californium. Each of the other choices also refers to elements with distinct electron configurations that do not match the given configuration, leading