When solid CO2 (dry ice) is allowed to come to equilibrium in a closed constant volume container at room temperature (300K),

1. the pressure rises until it reaches 1 atm

2. the pressure rises until a liquid-gas equilibrium is reached.

3. the pressure does not change.

4. the pressure rises until a liquid-solid equilibrium is reached

6 answers

2. the pressure rises until a liquid-gas equilibrium is reached.

A real life example of this is fire extinguishers which store CO2 as a liquid at room temperature at really high pressures.
Im just a student, but I think that as the dry ice sublimes into gas at low pressures, the pressure rises to a point where liquid can form. Eventually all the solid gets converted to liquid. the liquid CO2 warms to 300K and at this point an equilibrium is reached between liquid and the gas responsible for the extremely high pressures.
All I know is that Marcus is wrong because solids don't have to become liquids before they become gas. That is what is the case with dry ice. It becomes a gas before it has the time to go to a liquid.
Marcus is right, Josie. I don't really understand it either but he is correct.
jose` is wrong
All I know is that Josie is wrong because I just do.
The answer is liquid-gas equilibrium because of the temperature. at 300K, the solid CO2 sublimates into a gas; however, in order to maintain vp, the pressure increases, condensing the gas into liquid CO2 and creating a liquid gas equilibrium. At a lower temperature (below freezing) it could be a solid-gas equilibrium. Another way to look at it is with a CO2 phase diagram