Solution Found!
Bismuth is used to calibrate instruments employed in
Chapter 11, Problem 80P(choose chapter or problem)
Because bismuth has several well-characterized solid, crystalline phases, it is used to calibrate instruments employed in high-pressure studies. The following phase diagram for bismuth shows the liquid phase and five different solid phases stable above \(1 katm\) (\(1000 atm\)) and up to \(300^{\circ} \mathrm{C}\). (a) Which solid phases are stable at \(25^{\circ} \mathrm{C}\)? (b) Which phase is stable at \(50 katm\) and \(175^{\circ} \mathrm{C}\)? (c) Identify the phase transitions that bismuth undergoes at \(200^{\circ} \mathrm{C}\) as the pressure is reduced from 100 to \(1 katm\). (d) What phases are present at each of the triple points?
Equation Transcription:
300°C
175°C
25°C
Text Transcription:
1 katm
1000 atm
300°C
175°C
25°C
50 katm
200°C
Questions & Answers
QUESTION:
Because bismuth has several well-characterized solid, crystalline phases, it is used to calibrate instruments employed in high-pressure studies. The following phase diagram for bismuth shows the liquid phase and five different solid phases stable above \(1 katm\) (\(1000 atm\)) and up to \(300^{\circ} \mathrm{C}\). (a) Which solid phases are stable at \(25^{\circ} \mathrm{C}\)? (b) Which phase is stable at \(50 katm\) and \(175^{\circ} \mathrm{C}\)? (c) Identify the phase transitions that bismuth undergoes at \(200^{\circ} \mathrm{C}\) as the pressure is reduced from 100 to \(1 katm\). (d) What phases are present at each of the triple points?
Equation Transcription:
300°C
175°C
25°C
Text Transcription:
1 katm
1000 atm
300°C
175°C
25°C
50 katm
200°C
ANSWER:
Solution 80P
Here we have to answer the following questions depends on the given diagram and data.
A phase diagram represents the change of phase of a substance at different conditions. It is the combination various phases such as liquid-gas, solid-liquid and solid-gas curves. Here each phase is represented in separate region. The two most important points in phase diagram is critical point and triple point.
Critical point is a point in which the liquid and gas curve ends. At this point the densities of liquid and vapor become equal.
Triple point is defined as the point at which the three phase transition curves meet. At this point all the three phases are always in equilibrium.
Step 1
Bismuth is used to calibrate instruments employed in high-pressure studies because it has several well-characterized crystalline phases. Its phase diagram (right) shows the liquid phase and five solid phases that are stable above 1 katm (1000 atm) and up to 300°C.
(a) We have to explain which solid phases are stable at 25°C.
At 25oC the stable solid phases are, phase I, II, III and V.