Chapter 8, Problem 8.5NP

(a)

Interpretation Introduction

Interpretation: The conditions need to be determined for the P-T curve for CO₂at which when the temperature is increased, the solid is first converted to the liquid and then to the gaseous state.

  

Concept Introduction: All substances can mainly exist in three phases; solid, liquid and gases. These three phases can convert into each other by the application of temperature and pressure such as by heating of solid, it converts to liquid and then gaseous state of matter.

Similarly, the gases can be compressed at high pressure to liquefy. The interconversion of three phases of substance can be show on the phase diagram. A triple point indicates the value of T and P at which all the three phases of a substance that is pressure, temperature and volume coexist. At this point, the fusion, sublimation and vaporization curve intersect each other.

(b)

Interpretation Introduction

Interpretation: The conditions at which the interface delineating liquid and gaseous phase is observed throughout the pressure range between 6 and 65 atm needs to be determined for the below P-T curve for ${\text{CO}}_{\text{2}}$ .

  

Concept Introduction: All substances can mainly exist in three phases; solid, liquid and gases. These three phases can convert into each other by the application of temperature and pressure such as by heating of solid, it converts to liquid and then gaseous state of matter.

Similarly, the gases can be compressed at high pressure to liquefy. The interconversion of three phases of substance can be show on the phase diagram. A triple point indicates the value of T and P at which all the three phases of a substance that is pressure, temperature and volume coexist. At this point, the fusion, sublimation and vaporization curve intersect each other.

(c)

Interpretation Introduction

Interpretation: The conditions at which the solid, liquid and gas phase coexist at equilibrium for the below P-T curve for ${\text{CO}}_{\text{2}}$ needs to be determined.

  

Concept Introduction: All substances can mainly exist in three phases; solid, liquid and gases. These three phases can convert into each other by the application of temperature and pressure such as by heating of solid, it converts to liquid and then gaseous state of matter.

Similarly, the gases can be compressed at high pressure to liquefy. The interconversion of three phases of substance can be show on the phase diagram. A triple point indicates the value of T and P at which all the three phases of a substance that is pressure, temperature and volume coexist. At this point, the fusion, sublimation and vaporization curve intersect each other.

(d)

Interpretation Introduction

Interpretation: The conditions at which only a liquid phase is observed in the pressure range from 10 to 50 atm needs to be determined for the below P-T curve for ${\text{CO}}_{\text{2}}$ .

  

Concept Introduction: All substances can mainly exist in three phases; solid, liquid and gases. These three phases can convert into each other by the application of temperature and pressure such as by heating of solid, it converts to liquid and then gaseous state of matter.

Similarly, the gases can be compressed at high pressure to liquefy. The interconversion of three phases of substance can be show on the phase diagram. A triple point indicates the value of T and P at which all the three phases of a substance that is pressure, temperature and volume coexist. At this point, the fusion, sublimation and vaporization curve intersect each other.

(e)

Interpretation Introduction

Interpretation: The conditions at which an increase in the temperature from - 80 to 20 °C converts the solid to gas with no intermediate liquid phase needs to be determined.

  

Concept Introduction: All substances can mainly exist in three phases; solid, liquid and gases. These three phases can convert into each other by the application of temperature and pressure such as by heating of solid, it converts to liquid and then gaseous state of matter.

Similarly, the gases can be compressed at high pressure to liquefy. The interconversion of three phases of substance can be show on the phase diagram. A triple point indicates the value of T and P at which all the three phases of a substance that is pressure, temperature and volume coexist. At this point, the fusion, sublimation and vaporization curve intersect each other.