posted by Kelly on .
Solid carbon dioxide (dry ice) goes from solid to gas at -78C. The molar heat of sublimation is 25.3 kj/mol. In one experiment 34.5g of dry ice are placed in an insulated isolated container with 500 g of water at 25C. What temp of the water is expected after all bubbles are gone? Specific heat of water is 4.184 J/g*C ??
I suppose we assume that the gas, after forming, does not cool the water on its way out of the system.
moles CO2 = 34.5g/44 = ??
?? moles CO2 x 25.3 kJ/mol = xx kJ to sublime the dry ice. Convert to joules.
[mass water x specific heat water x (Tfinal-25)] + xxJOULES = 0
Solve for Tfinal.