Question

study the following phase diagram of substance x. use this diagram to answer the following questions. suppose a small sample of pure x is held at 6. °c and 2.8 atm. what will be the state of the sample? suppose the temperature is held constant at 6. °c but the pressure is decreased by 0.8 atm. what will happen to the sample? suppose, on the other hand, the pressure is held constant at 2.8 atm but the temperature is decreased by 239. °c. what will happen to the sample?

Explanation:

Step1: Convert temperature to Kelvin

$T = 6^{\circ}C+273 = 279K$, $P = 2.8atm$. Locate this point on the phase - diagram. It is in the solid region.

Step2: New pressure calculation

The new pressure $P_{new}=2.8 - 0.8=2atm$ with $T = 279K$. Locate this point on the phase - diagram. It moves from solid to liquid, so it melts.

Step3: New temperature calculation

The new temperature $T_{new}=6 - 239=- 233^{\circ}C$, $T_{new}=-233 + 273 = 40K$ with $P = 2.8atm$. Locate this point on the phase - diagram. It remains in the solid state.

Answer:

Solid
Melts
Remains solid