The original phase and final phase of a substance are shown. Phase Transition Original Phase Final Phase Solid Liquid What most likely happened during the phase transition?

The question appears to speak to the process between Liquid and Solid phases of a substance and seeks to resolve what happened in between.

The short answer is that the solid melted.

Explanation:

Melting is the process of a solid becoming fluid. When the reverse happens, (that is a liquid being solid), is called solidification. There is a temperature at which substances take their liquid form. That temperature is called the melting point. The melting point of ice (that is the temperature at which it starts to turn back to water) for instance is 32 °F.

According to the mechanics of melting, the internal energy of the solid increases, because of exposure to heat and or pressure usually through the application of heat or pressure, which increases the substance's temperature to the melting point.

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a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.