Question

Dry ice is solid carbon dioxide. Instead of melting, solid carbon dioxide sublimes according to the following equation: CO2(s)→CO2(g). When dry ice is added to warm water, heat from the water causes the dry ice to sublime more quickly. The evaporating carbon dioxide produces a dense fog often used to create special effects. In a simple dry ice fog machine, dry ice is added to warm water in a Styrofoam cooler. The dry ice produces fog until it evaporates away, or until the water gets too cold to sublime the dry ice quickly enough.

Answer 1

Suppose that a small Styrofoam cooler holds 15.0 liters of water heated to 90∘C.

Calculate the mass of dry ice that should be added to the water so that the dry ice completely sublimes away when the water reaches 18∘C. Assume no heat loss to the surroundings.
Express your answer using two significant figures.

The change in enthalpy for dry ice sublimation is 33.9kJ