A single atom of lithium can combine with a single atom of iodine to create electron energy stability for both atoms. True or false?
True
true !!!!!!!!!!!!
Certainly not. The ionization energy of Li is 520 kJ/mol. This is the energy required to remove one electron from the Li atom to create Li+. The electron affinity of I is only 295 kJ/mol. This is the energy released when you allow an electron to join the I atom creating an I- anion. You can see that creating a single Li+ / I- pair by transferring one electron from the Li to the I atom costs you 520 - 295 = 225 kJ/mol. That is, the energy of a single pair of Li+/I- is 225 kJ/mol above the neutral Li/I pair. For this reason, Li+/i_ pair do not exist in the gas phase. What you're supposed to understand by getting this question right is that ionic substances, like LiI, depend for their stability on the very large amount of energy released when the ions form a regular crystalline lattice. The interactions between Li+ cations and I- anions IN THE SOLID CRYSTAL are very strong, and these are what stabilize the compound.
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