Based on the phase diagram of CO₂ shown in Figure 11.39(b), describe the state changes that occur when the temperature of CO₂ is increased from 190 K to 350 K at a constant pressure of (a) 1 atm

Verified step by step guidance

1. Identify the initial state of CO₂ at 190 K and 1 atm using the phase diagram.
2. Determine the phase boundary that CO₂ will cross first as the temperature increases from 190 K to 350 K at 1 atm.
3. Describe the state change that occurs when CO₂ crosses the first phase boundary (e.g., solid to gas).
4. Continue to increase the temperature and identify any additional phase boundaries crossed until reaching 350 K.
5. Describe any further state changes that occur as CO₂ crosses these additional phase boundaries.

Key Concepts

Phase Diagram

A phase diagram is a graphical representation that shows the states of a substance (solid, liquid, gas) at various temperatures and pressures. It helps visualize the conditions under which a substance exists in different phases and the transitions between these phases, such as melting, boiling, and sublimation.

State Changes

State changes refer to the transitions between different phases of matter, which occur due to changes in temperature and pressure. For CO2, these changes include sublimation (solid to gas), melting (solid to liquid), and vaporization (liquid to gas). Understanding these transitions is crucial for predicting the behavior of CO2 under varying conditions.

Critical Point

The critical point is the temperature and pressure at which the distinction between liquid and gas phases disappears. Beyond this point, the substance becomes a supercritical fluid, exhibiting properties of both gas and liquid. For CO2, knowing the critical point is essential for understanding its behavior at high temperatures and pressures.