A reaction was performed in which 1.500 g of camphor was reduced by an excess of sodium borohydride to make 1.036 g of isoborneol. Calculate the theoretical yield and percent yield for this reaction.

Respuesta :

Answer: The percent yield of the reaction is 68.16 %.

Explanation:

To calculate the number of moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]      .....(1)

  • For camphor:

Given mass of camphor = 1.500 g

Molar mass of camphor = 152.23 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of camphor}=\frac{1.500g}{152.23g/mol}=9.85\times 10^{-3}mol[/tex]

The chemical equation for the reaction of camphor and sodium borohydride follows:

[tex]\text{Camphor}+NaBH_4\rightarrow \text{Isoborneol}[/tex]

As, sodium borohydride is present in excess. It is an excess reagent. So, camphor is the limiting reagent because it limits the formation of products.

By Stoichiometry of the reaction:

1 mole of camphor produces 1 mole of isoborneol

So, [tex]9.85\times 10^{-3}mol[/tex] of camphor will produce = [tex]\frac{1}{1}\times 9.85\times 10^{-3}mol=9.85\times 10^{-3}mol[/tex] of isoborneol

  • Now, calculating the mass of isoborneol from equation 1, we get:

Molar mass of isoborneol = 154.25 g/mol

Moles of isoborneol = [tex]9.85\times 10^{-3}[/tex] moles

Putting values in equation 1, we get:

[tex]9.85\times 10^{-3}mol=\frac{\text{Mass of isoborneol}}{154.25g/mol}\\\\\text{Mass of isoborneol}=(9.85\times 10^{-3}mol\times 154.25g/mol)=1.52g[/tex]

  • To calculate the percentage yield of isoborneol, we use the equation:

[tex]\%\text{ yield}=\frac{\text{Experimental yield}}{\text{Theoretical yield}}\times 100[/tex]

Experimental yield of isoborneol = 1.036 g

Theoretical yield of isoborneol = 1.52 g

Putting values in above equation, we get:

[tex]\%\text{ yield of isoborneol}=\frac{1.036g}{1.52g}\times 100\\\\\% \text{yield of isoborneol}=68.16\%[/tex]

Hence, the percent yield of the reaction is 68.16 %.