The graph shows a phase change diagram.
(solid goes from 0-50 on a, b stays at 50, C rises to liquid 150, D stays at 150, and and e rises to 200)
What phase change is taking place as energy is lost at segment BA?
A.
melting
B.
freezing
C.
sublimation
D.
condensation
B. freezing
The correct answer is B. freezing.
In segment BA, the temperature remains constant at 50 degrees. This indicates that energy is being lost or removed from the substance. At this temperature, the substance is transitioning from a liquid phase to a solid phase, which is known as freezing.
To determine the phase change taking place as energy is lost at segment BA, we need to understand the different phase changes represented in the graph.
The vertical axis of the graph represents temperature, while the horizontal axis represents the amount of energy (or heat) added or removed.
Looking at the graph description, we can see that segment BA represents a decrease in temperature while energy is lost. This means that heat is being removed from the substance.
Now, let's analyze the possible phase changes:
A. Melting: This occurs when a solid substance changes into a liquid as heat is added. However, in segment BA, heat is being lost, not added, so melting is not occurring.
B. Freezing: This occurs when a liquid substance changes into a solid as heat is removed. Since the segment in question shows a decrease in temperature while energy is lost, freezing is the likely phase change taking place at segment BA. This would mean that the substance is transitioning from a liquid to a solid.
C. Sublimation: Sublimation occurs when a solid substance changes directly into a gas without going through the liquid phase. This phase change is not applicable in segment BA.
D. Condensation: Condensation occurs when a gas changes into a liquid as heat is removed. However, since segment BA represents a decrease in temperature, not pressure, condensation is not taking place.
So, the correct answer is B. Freezing, as energy is being lost and the substance is changing from a liquid to a solid.