An alternative definition of electronegativity is Electronegativity 5 constant (I. E. 2 E. A.) where I. E. is the ionization energy and E. A. is the elec-tron affinity using the sign conventions of this book. Use data in Chapter 12 to calculate the (I. E. 2 E. A.) term for F, Cl, Br, and I. Do these values show the same trend as the electronegativity values given in this chapter? The first ionization energies of the halogens are 1678, 1255, 1138, and 1007 kJ/ mol, respectively. (Hint: Choose a constant so that the electronegativity of fluorine equals 4.0. Using this constant, calculate relative electronega-tivities for the other halogens and compare to values given in the text.)