A student dehydrated 12 grams of 2-methylcyclohexene with 85% H3PO4. What are the theoretical and percent yields?
To calculate the theoretical yield, we need to determine the limiting reagent in the reaction and use stoichiometry to find the maximum amount of product that can be formed. The limiting reagent is the reactant that is completely consumed, thus determining the maximum product that can be obtained.
First, let's write the balanced chemical equation for the dehydration of 2-methylcyclohexene:
2-methylcyclohexene + H3PO4 → product
Now, let's calculate the moles of 2-methylcyclohexene and H3PO4:
Molar mass of 2-methylcyclohexene = 98.19 g/mol
Molar mass of H3PO4 = 97.99 g/mol
Number of moles of 2-methylcyclohexene = 12 g / (98.19 g/mol) ≈ 0.122 mol
Number of moles of H3PO4 = 85% of 12 g / (97.99 g/mol) ≈ 0.102 mol
From the balanced equation, we can see that the stoichiometric ratio between 2-methylcyclohexene and H3PO4 is 1:1. Therefore, the limiting reagent is H3PO4 because it is present in a smaller amount.
Since the stoichiometry is 1:1, the maximum amount of product that can be formed is equal to the number of moles of H3PO4, which is approximately 0.102 mol.
To calculate the theoretical yield in grams, we multiply the number of moles by the molar mass of the product:
Molar mass of product = ??? (Cannot be determined without more information)
Without information about the molecular formula or molar mass of the product, we cannot calculate the theoretical yield in grams. However, we can still determine the percent yield.
The percent yield is the ratio of the actual yield to the theoretical yield, multiplied by 100%:
Percent yield = (Actual yield / Theoretical yield) x 100%
To calculate the percent yield, we need the actual yield. If the actual yield is not given, then we cannot determine the percent yield.