[xe] 6s2 4f4 is the noble gas configuration for which element

Neodymium

Explanation:

The given element is:

          [Xe] 6s² 4f⁴

To solve this problem, we need to find the number of electrons in the element given;

  Xe  has 54 electrons already

  6s² 4f⁴  where:

                 letters are the orbitals

                 6 and 4 are the energy levels

                superscript are the number of electrons

  So,  2 + 4  = 6

 Total number of electrons  = 54 + 6  = 60

The element is Neodymium

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.