AP Chemistrymediummcq1 pt
Which change requires the most energy for 1.0 mol of water?
A.Vaporizing at 100 °C
B.Melting at 0 °C
C.Warming from 20 °C to 100 °C
D.Warming from 0 °C to 20 °C
Explanation
Core Concept
Vaporization (40.7 kJ/mol) far exceeds melting (6.01 kJ/mol) or any modest temperature rise, because it severs every intermolecular attraction.
Correct Answer
AVaporizing at 100 °C
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