## Chem. Equilibrium Part 1B Post-Module Assess. #44 [ENDORSED]

$PV=nRT$

Grace Lee 3G
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### Chem. Equilibrium Part 1B Post-Module Assess. #44

Calculate the concentration of CO(g) in mol.m^-3 at 423 K and 0.8 atm using R = 8.206 × 10-5 m^3.atm.K^-1.mol^-1 and assuming only CO(g) is present.

A. 23 mol.m-3

B. 2.3 mol.m-3

C. 0.23 mol.m-3

D. 4.6 mol.m-3

E. None of the above

After using the ideal gas law and cancelling out the units, I'm left with 23 m^3 mol^-1.
How do I convert my answer to mol.m^-3? Or did I mess up somewhere in the calculation?

Chem_Mod
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### Re: Chem. Equilibrium Part 1B Post-Module Assess. #44  [ENDORSED]

Check your work again.

Units should cancel. Remember that when a unit is in a fractional form, such as units for gas constant R, and it is in the denominator, it is like multiplying through by the reciprocal.

$PV = nRT$

$\frac{n}{V}=\frac{P}{RT}$

$\frac{n}{V} = \frac{(0.8\: \textup{atm})}{(8.206 \times 10^{-5}\: \textup{m}^{3}\cdot \textup{atm}/\textup{mol}\cdot \textup{K})(423\: \textup{K}))} = 23\: \textup{mol}/\textup{m}^{3}$