Answer
See the answer below.
Work Step by Step
Number of moles of $CO_2$
$12.0\ g\div 44.0\ g/mol=0.27\ mol$
a) Van der Waals equation:
$\left[P+a\left(\dfrac nV\right)^2\right](V-bn)=nRT$
$(P+1.06\ atm)×0.488\ L=6.67\ L.atm$
$P=12.6\ atm$
Ideal gas:
$PV=nRT$
$P=13.3\ atm$
Percent error:
$(13.3-12.6)/12.6×100\%=5.56\%$
b) Van der Waals equation:
$\left[P+a\left(\dfrac nV\right)^2\right](V-bn)=nRT$
$(P+1.06\ atm)×0.488\ L=4.54\ L.atm$
$P=8.23\ atm$
Ideal gas:
$PV=nRT$
$P=9.08\ atm$
Percent error:
$(9.08-8.23)/9.08×100\%=10.3\%$
