The lattice energy of CsF is -744 kJmol, whereas that of BaO is ...

Question

The lattice energy of CsF is -744 kJ>mol, whereas that of BaO is 
-3029 kJ>mol. Explain this large difference in lattice energy.

Accepted Answer

hey everyone in this example, we need to explain why there's a big difference between the lattice energy of magnesium oxide and lithium chloride. So what we want to consider is the product of our charges of our ions within our two molecules. So within magnesium oxide, we should recognize that we are consisting of the MG two plus cat eye on because we would recall that magnesium is located in group to a corresponding to a two plus charge, whereas oxygen located in Group six A Will correspond to a 2 - charge. And so we want to take the product of the charges by taking two Plus and multiplying that by -2. And this is going to give us a value because we have a negative being multiplied by a positive equal to -4. Now we're going to compare this to the ions that make up lithium chloride. And so we would recall that lithium is located in Group one A. On our periodic table corresponding to the L. I plus one catty on, whereas chlorine is located in Group seven A. On our periodic tables corresponding to the cl minus one an ion. And so to take the product of the charges here, we would have plus one Being multiplied to -1. And this would give us a value of positive, being multiplied by a negative, giving us -1 another negative. Now, as you can see, we would say that we have a greater magnitude of negative charge compared to our lithium chloride which only produced a magnitude of the electrical charge Products Being -1. So because we have the greater magnitude associated with our ions in magnesium oxide, we would go ahead and say that it supports a larger lattice energy due to the fact that magnesium oxide is going to be therefore more stable and more able to release more energy. And so we would go ahead and based on this explanation, confirm that choice. B is going to be the most correct choice to explain as to why we have such a large difference from the lattice energy between magnesium oxide and lithium chloride. And again, that is due to the fact that the magnitude of the potential of the ions in magnesium ion in magnesium oxide is greater than the ions of lithium chloride, which ions produced a Product of their charges equal to only negative one here. So B is the final choice. If you have any questions, please leave them down below. But I hope my explanation was clear, and I will see everyone in the next practice video.

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