Question

Suppose a sample of Carbon Dioxide and a separate sample of water are held each at a temperature of -80°C and a pressure of 5.00 atm. The temperature of each sample is gradually increased to 10°C while keeping the pressure constant. What will happen to each sample? Select the correct answer. The water will undergo: melting, freezing, sublimation, deposition, vaporization, condensation. The carbon dioxide will undergo: melting, freezing, sublimation, deposition, vaporization, condensation.

Answer 1

Answer: Carbon dioxide will undergo sublimation and water will undergo melting. When the temperature of a substance is increased while keeping the pressure constant, the substance will undergo a phase change if the temperature is greater than its melting or sublimation point. Since the melting point of water is 0°C and the sublimation point of carbon dioxide is -78.5°C, both substances will undergo a phase change as the temperature increases from -80°C to 10°C.