Phase Change Chemistry Example 3

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Example 3

easy
What phase change occurs when dry ice (CO2\text{CO}_2) goes directly from solid to gas?

Solution

  1. 1
    The direct conversion from solid to gas is called sublimation.
  2. 2
    Dry ice sublimes at −78.5°C-78.5°\text{C} at atmospheric pressure, which is why it 'disappears' without leaving a liquid.

Answer

Sublimation\text{Sublimation}
Sublimation occurs when the vapor pressure of the solid exceeds atmospheric pressure before the melting point is reached. This is a characteristic property of CO2\text{CO}_2 at standard pressure.

About Phase Change

A physical transition from one state of matter to another caused by adding or removing thermal energy, during which the temperature remains constant as energy.

Learn more about Phase Change →

More Phase Change Examples

Example 1 easy

Name the six phase changes and indicate whether each absorbs or releases energy.

Example 2 medium

Why does the temperature remain constant during a phase change, even though heat is being added?

Example 4 hard

A heating curve shows a substance warming from [formula] to [formula]. It has a melting point of [fo

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