Answer:
The true statements include;
- The sample is initially a gas.
- The final state of the substance is a solid.
- One or more phase changes will occur.
The untrue/false statements include;
- The liquid initially present will vaporize.
- The final state of the substance is a liquid.
Explanation:
A couple pieces of informatton on Fluorine is imitially provided.
The substance fluorine has the following properties: normal melting point: 53.5 K normal boiling point: 85.0 K triple point: 1.6×10-4 atm, 53.4 K critical point: 55 atm, 144.1 K
So, a question is now attached about a sample of Fluorine. A sample of fluorine at a pressure of 1.00 atm and a temperature of 90.3 K is cooled at constant pressure to a temperature of 49.3 K.
We are then told to examine a group of options to find the ones that are correct/apply.
Taking the options one at a time
- The sample is initially a gas.
The initial state of the Fluorine sample has its temperature at 90.3 K, which is above the gas' boiling point. Hence, the sample can be concluded to initially be a gas.
- The liquid initially present will vaporize.
The sample doesn't initially contain liquid. And even of it did, the temperature is cooled, not heated , Hence, this statement is wrong.
- The final state of the substance is a solid.
The sample of Fluorine moves from a temperature higher than boiling point (85.0 K), with the sample in gaseous form, to one that is at a lower temperature (49.3 K) than the gas' normal melting point (53.5 K).
At temperatures lower than melting point, a substance exists in the solid form. Hence, this statement is true. The final state of the substance is solid.
- One or more phase changes will occur.
In moving from 90.3 K to 49.3 K for the sample and passing through the substance's boiling and melting points (85.0 K and 53.5 K respectively) along the way, it is logical to conclude that there would be one or more phase changes will occur. This statement is true.
- The final state of the substance is a liquid.
This is false as we already established that the final state of the substance is a solid. Hence, this statement is false.
Hope this Helps!!!
