Tungsten Ionization Energy

The Tungsten Ionization Energy is the energy required to remove from atom one mole of electrons with subsequent production of positively charged ion of Tungsten.
W -> W⁺ + e^-
This process can be repeated many times, but the energy cost is increased dramatically. The general equation for the Tungsten is:
W^N+ -> W^(N+1)+ + e^-

W -> W¹⁺ = 770 kJ/mol = 184.21 Kcal/mol
W¹⁺ -> W²⁺ = 1700 kJ/mol = 406.70 Kcal/mol
W²⁺ -> W³⁺ = 2300 kJ/mol = 550.24 Kcal/mol
W³⁺ -> W⁴⁺ = 3400 kJ/mol = 813.40 Kcal/mol
W⁴⁺ -> W⁵⁺ = 4600 kJ/mol = 1100.48 Kcal/mol
W⁵⁺ -> W⁶⁺ = 5900 kJ/mol = 1411.48 Kcal/mol