Ask A Scientist© Chemistry Archive

name         Adam W.
status       educator
age          20s

Question -   What is the volume of 1 kg of Carbon Dioxide at normal
(sea-level) pressure?

----------------------
Adam,

Are we to assume you mean CO2 gas? if so, then (neglecting sig figs):

1 mole of CO2 is 44 g

(1000g CO2) / ( 44 g/ mole) = 22.73 moles CO2

1 mole any ideal gas @ STP = 22.4 L

(22.73 moles CO2)(22.4 L/m) = 509.1 L

If you are referring to solid CO2 at a density of 1.56 g / cm^3 and at -79
C, then:

d = m/V and V = m/d

V = (1000 g solid / (1.56 g/cm^3) = 641 cm^3 solid CO2

A block about 8.6 cm on each edge.

It would not hold that size for long because at "normal (sea-level) pressure"
it would sublime away.

Regards,
ProfHoff
=========================================================
At S.T.P. (i.e. 273.15 Kelvin & 1 atm ) the ideal gas law ( which works
pretty well up to about 10 atm for non-reactive gases gives ) : V = n x R x
T / P = (1000/44) x 0.08205 x 273.15 / 1 =
509.4 liters. For reasons unknown, I used T = 298 (i.e. about 25 C.) not T =
273.15 (i.e. about 0 C.). I'm still not sure where the "answer" = 537.592
liters came from.

Vince Calder
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Hello Adam :

          The molecular weight of CO2 is 44.0098 grams per mole. Dividing
this by the density of CO2 at 25 degrees Centigrade and 1
atmosphere,  0.0019 grams per cubic centimeter, gives a volume of


                                   44.0098 grams per mole
                          --------------------------------------------------
= 23,163 cubic centimeters per mole
                          0.0019 grams per cubic centimeter

This can be compared with an ideal gas, whose volume is given by

         n*R*T
V = ---------
            P

which gives a value of 24,456 cubic centimeters per mole. In case you're
interested, the equation of state I used to calculate the density of CO2 is
given in

Huang, F., Li, M., Lee, L., and Starling, K., 1985, An Accurate Equation of
State for Carbon Dioxide, Journal of Chemical Engineering of Japan, Vol.
18, No. 6.


Cheers,

Jim Rubin
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