Summary

• Kinetic theory of gases
• Elastic properties of solids
• Latent heat

• Reading Quiz



• Latent heat
  Example #1
  
  
  

  ---

  Chapter 18

  ---

  
  
• Laws of Thermodynamics summary
  • 0^th Law: thermal equilibrium
  • 1^st Law: conserve energy
  • 2^nd Law: increase entropy
  • 3^rd Law: T > 0 always
  
  
  
  
  
  
  
  
  
  

Walker4e
Reading quiz One gram of steam at 100°C that comes in contact with your skin will cause a more serious burn than one gram of water at 100°C because

1. the steam first emits the latent heat of vaporization as it condenses to water.
2. the steam requires the latent heat of fusion to be delivered by your skin.
3. the steam chemically reacts with your skin cells but the water does not.
4. the steam has a higher specific heat than water and therefore delivers more energy.

Answer















klm
How many −10°C, 25-g ice cubes should you add to cool a 2-L bottle of warm (25°C) soda down to 5°C? Assume c_soda = c_water
A. 4
B. 7
C. 10
D. 18
Answer















 



A. the steam first emits the latent heat of vaporization as it condenses to water.

A gram of steam will emit 539 cal when it condenses to water at 100°C, and another 63 cal as it cools down to 37°C. A gram of water at 100°C will only deliver the 63 cal as it cools down. So the steam delivers almost ten times more energy than does the water, causing a much more serious burn.
























 



D. 18