Find the best tutors and institutes for Class 11 Tuition
Q11.21(c):
Answer the following questions based on the P-T phase diagram of carbon dioxide: (c) What are the critical temperature and pressure for $CO_2$ ? What is their significance ?
Solution :
1. Identification of Critical Parameters for $CO_2$
The critical point on a $P-T$ phase diagram represents the terminal point of the liquid-gas equilibrium curve. Beyond this point, the physical distinction between liquid and gaseous phases vanishes. For carbon dioxide ($CO_2$), experimental measurements define the following critical values:
- Critical Temperature ($T_c$): $31.1 \, ^\circ\text{C}$ (or $304.1 \, \text{K}$)
- Critical Pressure ($P_c$): $73.0 \, \text{atm}$ (or approximately $7.39 \times 10^6 \, \text{Pa}$)
2. Conceptual Significance of the Critical Point
The critical point is a state of matter where the density of the gas phase equals the density of the liquid phase. The significance is categorized into two primary physical implications:
- Disappearance of Phase Boundary: At temperatures above $T_c$, $CO_2$ exists as a supercritical fluid. In this state, it is impossible to liquefy the gas regardless of the amount of pressure applied [Per the Kinetic Molecular Theory of Gases].
- Non-liquefaction Constraint: Below the critical temperature, $CO_2$ can be liquefied by applying sufficient pressure to move the state across the liquid-vapor equilibrium line. However, at $T > T_c$, the gas occupies a single, homogeneous state that possesses properties of both a gas (low viscosity) and a liquid (high solvent capability).
3. Visual Representation of the Phase Diagram
4. Practical Implications in Thermodynamics
| Parameter | Physical Significance |
|---|---|
| $T > T_c$ | The gas cannot be liquefied, regardless of compression. |
| $P > P_c$ | The system behaves as a supercritical fluid with unique solvent properties. |
Final Solution: The critical temperature of $CO_2$ is $31.1 \, ^\circ\text{C}$ and the critical pressure is $73.0 \, \text{atm}$. Their significance lies in the fact that above these values, $CO_2$ exists only as a supercritical fluid, and it is impossible to condense the gas into a liquid state by increasing pressure alone.
More Questions from Class 11 Physics Thermal Properties of Matter ADDITIONAL EXERCISES
- Q11.21(a): Answer the following questions based on the P-T phase diagram of carbon dioxide: (a) At what temperature and pressure can the solid, liquid and vapour phases of $CO_2$ co-exist in equilibrium ?
- Q11.21(b): Answer the following questions based on the P-T phase diagram of carbon dioxide: (b) What is the effect of decrease of pressure on the fusion and boiling point of $CO_2$ ?
- Q11.21(d): Answer the following questions based on the P-T phase diagram of carbon dioxide: (d) Is $CO_2$ solid, liquid or gas at (a) –70 °C under 1 atm, (b) –60 °C under 10 atm, (c) 15 °C under 56 atm ?
- Q11.22(a): Answer the following questions based on the P – T phase diagram of $CO_2$: (a) $CO_2$ at 1 atm pressure and temperature – 60 °C is compressed isothermally. Does it go through a liquid phase ?
- Q11.22(b): Answer the following questions based on the P – T phase diagram of $CO_2$: (b) What happens when $CO_2$ at 4 atm pressure is cooled from room temperature at constant pressure ?
- Q11.22(c): Answer the following questions based on the P – T phase diagram of $CO_2$: (c) Describe qualitatively the changes in a given mass of solid $CO_2$ at 10 atm pressure and temperature –65 °C as it is heated up to room temperature at constant pressure.
- Q11.22(d): Answer the following questions based on the P – T phase diagram of $CO_2$: (d) $CO_2$ is heated to a temperature 70 °C and compressed isothermally. What changes in its properties do you expect to observe ?
CBSE Solutions for Class 11 Physics Thermal Properties of Matter
Chapters in CBSE - Class 11 Physics
Top Tutors who teach Thermal Properties of Matter
Top Tutor
Sector 38, Chandigarh
8 yrs of
Exp
1 student
10 hrs of classes completed
Online Classes
i am a teacher....I am giving home/online tuition since last 8years..I have a degree in masters of biotechnology...My key skills are best in competition as well as theoratical classes...I worked as biology project head in various institute as well as in various schools for preparing kids for NEET and for other medical entrance exams.
Top Tutor
Besa, Nagpur
8 yrs of
Exp
10 hrs of classes completed
2000
per hour
Student's Home
Tutor's home
I believe in learning,When I am teaching I get a dual opportunity of learning as well as teaching. I always synthesis more on Power of Thinking, Which is followed by the act. I have experience conducting training sessions For the professionals as well the students. When I was in school,I have won prizes in many debate Competitions. I always motivate people to achieve their real dreams.
Top Tutor
Durlavganj, Chandrakona Road
12 yrs of
Exp
6 students
262 hrs of classes completed
500
per hour
Online Classes
Krishnendu Gorai – Expert Physics Tutor for Class 12, JEE, and NEET. About Me: I am Krishnendu Gorai, a dedicated and experienced Physics educator with over 10 years of teaching experience in CBSE and competitive exam preparation. I specialize in teaching Class 11 and 12 Physics, along with focused coaching for JEE (Main and Advanced) and NEET aspirants. My goal is to make Physics simple, logical, and scoring for every student. I believe that with the right guidance, any student can master Physics and perform excellently in both board exams and competitive exams. Subjects and Courses Offered: Class 12 Physics (CBSE and State Boards): - Electrostatics - Current Electricity - Magnetic Effects of Current - Electromagnetic Induction - Alternating Current - Ray and Wave Optics - Modern Physics - Semiconductor Electronics JEE (Main and Advanced) Physics: - Concept-based preparation - Advanced numerical problem solving - Previous year questions and mock tests - Strategy for high-rank performance NEET Physics Preparation: - NCERT-focused theory - Important formulas and shortcuts - Assertion-reason and MCQ practice - Full syllabus revision and test series.
The classes are progressing well; however, there is an urgent need to begin conducting regular assessments, which have not yet been implemented.
Top Tutor
A B Road, Indore
4 yrs of
Exp
1 student
Online Classes
Student's Home
I am a professional tutor with four years of experience in teaching. Having a degree in M.Com from Vikram University and an MBA from IMD Indore I have also completed my B.Ed from IPS Academy Indore in the year 2015. I teach Spoken English, Accountancy, Business Studies, Economics, Statistics, Secretarial Practices, etc., for State, CBSE, ISC/ICSE Board students. I am well versed in English, Hindi and can take classes at Student's Home, My Home and Online Classes via video chat, skype, google hangout, etc.
Super Tutor
Jayanagar East, Bangalore
4 yrs of
Exp
47 students
5887 hrs of classes completed
250
per hour
Online Classes
Tutor's home
I take classes for grade 11 of Karnataka State PUC, CBSE, ISC, NIOS and Cambridge or IGCSE AS Levels. I have 4 years of teaching experience.
Attending this introductory chemistry demonstration session offered an insightful look into the program's academic standard. The instructor demonstrated excellent command of the subject matter, skillfully translating intricate chemical principles into accessible intellectual concepts.
Other Subjects in CBSE - Class 11
Download free CBSE - Class 11 Physics Thermal Properties of Matter ADDITIONAL EXERCISES worksheets
Download Now
