CHAPTER TEN

109. A single hydrogen bond in H2O has a strength of 21 kJ/mol. Each H2O molecule forms two H bonds. Thus, it should take 42 kJ/mol of energy to break all of the H bonds in water. Consider the phase transitions: It takes a total of 46.7 kJ/mol to convert solid H2O to vapor (ΔHsub). ................
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