Which substance do you expect to have the greatest lattice energy: mgf2, caf2, or zro2?

The compound which consists of two ions that have a great difference in electronegativity is the one with the greatest lattice energy. The periodic trend for electronegativity is: increases across a period, and decreases down a group. From this estimate, we can deduce that CaF₂ has the greatest lattice energy.

You would be correct, boiling water does disinfect contamination.    the property of disinfecting means to kill  germs, bacteria and other pathogens or contamination  that might cause an infection or cause a person to become sickly. a couple methods of disinfecting are using soap, other cleaning supplies or by simply "boiling" the contaminate.  the reason why boiling water disinfects certain attributes is because some cells cannot survive the heat and pressure.