Question

Which element has the electron configuration [Xe] 6s2 4f14 5d10 6p2?

Answer 1

do you know what the [Xe] in brackets means? It's the noble gas "core" layers of electrons.

Answer 2

Basically, 'Xe's electrons ADD the electrons in the shells you have after [Xe]

Xe's electron (atomic) number: 54
Number of electrons in the shells after [Xe] in your question: 28

54 + 28 = 82 electrons

Look on the periodic table and see what element has an atomic number of 82, and that will be your answer :)