The triple point of H₂O is at 4.58 mmHg and +0.01°C. Some H₂O at -50°C is heated to 120°C at a constant pressure of 0.5 atm. The changes of state occurring in this process are:

Question

Quizplus · Accepted Answer

At the initial temperature of -50°C, H₂O is in the solid state. Heating it to 120°C at a constant pressure of 0.5 atm, first the solid will change to liquid as the temperature reaches the melting point. Then, as the temperature continues to increase, the liquid will change to gas as it reaches the boiling point. Therefore, the changes of state occurring in this process are solid to liquid to gas, which corresponds to choice B.

The Triple Point of H2O Is at 4

The Triple Point of H₂O Is at 4