Question

6.407 g of solid CO₂ (44.01 g/mol) is put in an empty sealed 3.45 x 10³ mL container at a temperature of 305.7-K. When all the solid CO₂ becomes gas, what will be the pressure (in bar) in the container? ( R = 0.08206 L.atm/mol.K)

Answer 1

Given data in above 

Mass of CO₂ (w) = 6.407 g 

Molar mass of CO₂ (M)= 44.01 g/mol 

Volume of container (V) = 3.45×10³ mL

1 L = 1000 mL 

Then , 3.45×10³ mL = (1L÷1000 mL)×3.45×10³ mL 

 = 3.45 L 

Temperature (K) = 305.7 K 

R ( Gas constant) = 0.08206 L .atm /mol. K 

Calculation of pressure of the CO₂ gas in container .

  We first calculate moles (n) of CO₂ 

$n =\frac {w}{M}$

 = $\frac{6.407 g}{44.01 g}$  

 = 0.15 mol 

  Now, using ideal gas equation to calculate pressure of gas in the container. 

PV= nRT 

P =  $\frac{nRT}{V }$

 $=\frac{0.15 mol×0.08206 L/ atm /mol/K×305.7 K) }{3.45 L }$

 = $\frac{3.76 atm}{3.45}$

 = 1.09 atm 

P = 1.09 atm 

We know that 

1 atm = 1.013 bar 

Then ,  $1.09 atm =\frac{1.013 bar× 1.09 atm }{1atm}$

        = 1.104 bar 

Hence, the pressure of the CO₂ gas in the container is 1.104 bar .