Question

When ethane, c2h6, reacts with chlorine, cl2, the main product is c2h5cl, but other products containing cl such as c2h4cl2 are also obtained in small quantities. c2h6 + cl2 c2h5cl + hcl the formation of these other products reduces the yield of c2h5cl. using the stoichiometry given in the chemical formula above, calculate the percent yield of c2h5cl if the reaction of 150. g of c2h6 with 205 g of cl2 produced 172 g of c2h5cl?

Answer 1

To calculate the percent yield of C₂H₅Cl, we first determined the limiting reactant, which is Cl₂, then calculated the theoretical yield based on this limiting reactant, and finally found the percent yield to be 68.96% by comparing the actual yield to the theoretical yield.

Step-by-step explanation:

To calculate the percent yield of C₂H₅Cl, we first need to determine the theoretical yield based on the stoichiometry of the balanced chemical equation. Since the question provides masses of both reactants, we must find out which reactant is the limiting reactant as it will determine the maximum amount of product that can be formed.

The reaction between ethane (C₂H₆) and chlorine (Cl₂) is:

• C₂H₆ + Cl₂ → C₂H₅Cl + HCl

Next, we convert the given masses of reactants to moles using their molar masses:

• Moles of C₂H₆ = 150 g / (2*12.01 + 6*1.008) g/mol = 6.803 moles
• Moles of Cl₂ = 205 g / (2*35.45) g/mol = 2.891 moles

According to the stoichiometry of the reaction, 1 mole of C₂H₆ reacts with 1 mole of Cl₂. Therefore, Cl₂ is the limiting reactant since there are fewer moles of it compared to C₂H₆.

We can then calculate the theoretical yield of C₂H₅Cl produced from the limiting reactant Cl₂:

• Theoretical yield of C₂H₅Cl = Moles of Cl₂ * Molar mass of C₂H₅Cl = 2.891 moles * (2*12.01 + 5*1.008 + 35.45) g/mol = 249.46 g

Finally, we calculate the percent yield using the actual yield and the theoretical yield:

• Percent yield = (Actual yield / Theoretical yield) * 100 = (172 g / 249.46 g) * 100 = 68.96%

The percent yield of C₂H₅Cl is therefore 68.96%.

Answer 2

Step-by-step explanation:

Theoretical yield is the amount supposedly produced by the reaction if it was complete. The balanced chemical reaction is:

C2H6 + Cl2 = C2H5Cl + HCl

We use the amounts given for the reactants as the starting point of the calculations to determine the limiting reactant. We do as follows:

150 g C2H6 ( 1 mol / 30.08 g ) = 4.987 mol

205 g Cl2 ( 1 mol / 70.9 g ) = 2.891 mol

Therefore, the limiting reactant would be Cl2 since it would be consumed completely first in the reaction. We use this for the theoretical yield.

2.891 mol Cl2 ( 1 mol C2H5Cl / 1 mol Cl2 ) = 2.891 mol C2H5Cl (THEORETICAL YIELD)

172 g ( 1 mol / 64.52 g ) = 2.666 mol C2H5Cl ( ACTUAL YIELD)

Percent yield = 2.666 / 2.891 x 100 = 92.21%