Question

Consider the reaction of cyclohexanol and an acid catalyst to obtain cyclohexene.

Answer 1

Answer : The percent yield of the reaction is, 86.5 %

Solution : Given,

Mass of Cyclohexanol = 3.1 g

Molar mass of Cyclohexanol = 100.16 g/mole

Molar mass of Cyclohexene = 82.14 g/mole

First we have to calculate the moles of Cyclohexanol.

$\text{ Moles of Cyclohexanol }=\frac{\text{ Mass of Cyclohexanol }}{\text{ Molar mass of Cyclohexanol }}=\frac{3.1g}{100.16g/mole}=0.03095moles$

Now we have to calculate the moles of Cyclohexene.

The balanced chemical reaction is,

$Cyclohexanol\rightarrow Cyclohexene$

From the reaction, we conclude that

As, 1 mole of Cyclohexanol react to give 1 mole of Cyclohexene

So, 0.03095 mole of Cyclohexanol react to give 0.03095 mole of Cyclohexene

Now we have to calculate the mass of Cyclohexene.

$\text{ Mass of Cyclohexene}=\text{ Moles of Cyclohexene}\times \text{ Molar mass of Cyclohexene}$

$\text{ Mass of Cyclohexene}=(0.03095moles)\times (82.14g/mole)=2.542g$

Theoretical yield of Cyclohexene = 2.542 g

Experimental yield of Cyclohexene = 2.2 g

Now we have to calculate the percent yield of reaction.

$\% \text{ yield of reaction}=\frac{\text{ Experimental yield of Cyclohexene}}{\text{ Theretical yield of Cyclohexene}}\times 100$

$\% \text{ yield of reaction}=\frac{2.2g}{2.542g}\times 100=86.5\%$

Therefore, the percent yield of the reaction is, 86.5 %