Q13-124CP - Chemistry: Molecular Nature Of Matter And Change

Question

Air in a smoky bar contains $4.0\times {10}^{-6}mol/L$of CO. What mass of CO is inhaled by a bartender who respires at a rate of 11 L/min during an 8.0-h shift?

Step-by-Step Solution

Answer

Mass of CO inhaled by a bartender is 0.59g.

Step 1: Molarity

Molarity is defined as number of moles per litre solution.

molarity =no. of moles of solute

                   volume of solvent$molarity=\frac{(no.\hspace{0.33em}of\hspace{0.33em}moles\hspace{0.33em}of\hspace{0.33em}solute)}{(volume\hspace{0.33em}of\hspace{0.33em}solvent)}$

Volume of air $=11\hspace{0.33em}L/min\times 8h=11\hspace{0.33em}L/min\times 8\times 60 min= 5280L$ 

Hence, the number of moles CO of can be calculated as follow;

 $number\hspace{0.33em}of\hspace{0.33em}moles\hspace{0.33em}of\hspace{0.33em}CO=molarity\times volume\hspace{0.33em}of\hspace{0.33em}air$

Molarity of CO is $4.0\times {10}^{-6}mol/L$   and volume of air is 5280L.

$$\begin{gathered} number of moles of CO =4.0\times {10}^{-6}mol/L\times 5280L \\ =0.02112moles \end{gathered}$$

 

Step 2: Mass of CO

Mass of CO can be calculated by multiplying number of moles of CO and molecular mass of CO.

Molecular mass of$CO=12+16=28$

$$\begin{gathered} mass of CO=no. of moles of CO\times molecular mass of CO \\ =0.02112mol\times 28g/mol \\ =0.59g \end{gathered}$$