Basic Thermodynamics ~ J. Pohl © | www.THERMOspokenhere.com
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Ice, as frozen (solid) water is commonly purchased to chill beveradges. Ice is in great need in times of power outage to preserve foods. Dry ice, frozen (solid) carbon dioxide, called "dry ice" is a commercially supplied alternative to "ice" of frozen water.
WATER: (Initial State - 1) sat. solid at 0°C and 1 atm. |
WATER: (Melted) sat. liquid at 0°C and 1 atm. |
WATER: (Final State - 2) at 25°C and 1 atm. |
T = 0°C vs = 1.09 cm3/g hs = hs* |
T = 0°C vf = 1.00 cm3/g hf ≡ hs + hsf = hs* + 333 J/g |
T = 25°C v = 1.00 cm3/g h = hf + cavg( T - 0°C) = hs* + hsf + cavg(T - 0°C) = hs* + 333 J/g + 4.2 J/(g °C)(25 - 0)°C |
CARBON DIOXIDE: (Initial State - 1) sat solid at -79°C and 1 atm. |
CARBON DIOXIDE: (Sublimed) sat. gas at -79°C and 1 atm |
CARBON DIOXIDE: (Ideal Gas) at 25°C and 1 atm |
T = -79°C vs = 0.64 cm3/g hs = hs* |
T = -79 °C vg = 113 cm3/g hg ≡ hs + hsg hg = hs* + 573 J/g |
T = 25°C v = 559 cm3/g cp = 0.85 J/g°C cv = 0.66 J/g°C h = hg + cp,avg(T - 0°C) = hs* + hsf + cavg(T - 0°C) = hs* + 333 J/g + 4.2 J/(g °C)(25 - 0)°C |