Phase Diagrams of Water and Carbon Dioxide Assignment

A phase diagram tells you what phase a substance is in at various pressures and temperatures. Phase diagrams are created based on the results of many observations of a substance.

Use the phase diagrams to answer the following questions.

Use the phase diagrams to determine the most stable phase of water and carbon dioxide at room temperature (25°C) and atmospheric pressure (101 kPa).

Do these predictions agree with your experience?

Use the phase diagram of water to answer the following:

At what temperature does ice melt at 101 kPa?

At what temperature does water boil at 101 kPa?

Albuquerque, New Mexico, is approximately 5,500 feet above sea level, which means the normal atmospheric pressure there is less than 101 kPa.

i. In Albuquerque, will water freeze at a lower temperature or a higher temperature than at 101 kPa?

ii. In Albuquerque, will water boil at a higher or lower temperature than at 101 kPa?

Suppose you attached a bucket of water at 25°C to a weather balloon and let it rise to great heights. What would happen to the phase of the water, assuming the water stayed at 25°C? Use the phase diagram of water from the previous page to support your answer.

When dry ice was placed in a sealed bag, the bag filled with gas. Based on the phase diagram of carbon dioxide, what process is causing the bag to fill? Use the phase diagram to support your answer.

At room temperature, at what pressure would you expect dry ice to melt instead of sublime?

Why do you think solid carbon dioxide is called dry ice?

Based on the phase diagrams, which particles do you think are more strongly attracted to one another, those in water or those in carbon dioxide?