The atomic number of an element is 71. is this element diamagnetic or paramagnetic?

The element with atomic number 71 (lutetium) is paramagnetic

This is because all its electrons is not paired. lutetium has electron configuration of (Xe) 4f^14 5d^1 6S^2

Its 5d sub shell is not paired since the d sub shell can accommodate a total of 10 electrons hence lutetium is paramagnetic