Question

A piece of solid carbon dioxide, with a mass of 7.4 g, is placed in a 4.0-L otherwise empty container at 27°C.
(a) What is the pressure in the container after all the carbon dioxide vaporizes?
1.0atm
(b) If 7.4 g solid carbon dioxide were placed in the same container but it already contained air at 740 torr, what would be the partial pressure of carbon dioxide?
.97atm
(c) What would be the total pressure in the container after the carbon dioxide vaporizes?
??? atm

Answer 1

a. My calculator reads 1.035 atm which I would round to 1.0 to two s.f.
b. I thought Dalton's law said that the partial pressure of a gas is the pressure of the gas as if it were the only gas in the container. So why would the answer for b and a not be the same?
c. Total pressure = sum partial pressure of each gas.