Aspirin (acetylsalicylic acid) is prepared by heating salicylic acid, C7 H6 O3, with acetic anhy

Aspirin (acetylsalicylic acid) is prepared by heating...

Aspirin (acetylsalicylic acid) is prepared by heating salicylic acid, $\mathrm{C}_{7} \mathrm{H}_{6} \mathrm{O}_{3},$ with acetic anhydride, $\mathrm{C}_{4} \mathrm{H}_{6} \mathrm{O}_{3} .$ The other product is acetic acid, $\mathrm{C}_{2} \mathrm{H}_{4} \mathrm{O}_{2}$ $$ \mathrm{C}_{7} \mathrm{H}_{6} \mathrm{O}_{3}+\mathrm{C}_{4} \mathrm{H}_{6} \mathrm{O}_{3} \longrightarrow \mathrm{C}_{9} \mathrm{H}_{8} \mathrm{O}_{4}+\mathrm{C}_{2} \mathrm{H}_{4} \mathrm{O}_{2} $$ What is the theoretical yield (in grams) of aspirin, $\mathrm{C}_{9} \mathrm{H}_{8} \mathrm{O}_{4},$ when $2.00 \mathrm{~g}$ of salicylic acid is heated with $4.00 \mathrm{~g}$ of acetic anhydride? If the actual yield of aspirin is $1.86 \mathrm{~g}$, what is the percentage yield?

Aspirin (acetylsalicylic acid) is prepared by heating salicylic acid, $\mathrm{C}_{7} \mathrm{H}_{6} \mathrm{O}_{3},$ with acetic anhydride, $\mathrm{C}_{4} \mathrm{H}_{6} \mathrm{O}_{3} .$ The other product is acetic acid, $\mathrm{C}_{2} \mathrm{H}_{4} \mathrm{O}_{2}$
$$
\mathrm{C}_{7} \mathrm{H}_{6} \mathrm{O}_{3}+\mathrm{C}_{4} \mathrm{H}_{6} \mathrm{O}_{3} \longrightarrow \mathrm{C}_{9} \mathrm{H}_{8} \mathrm{O}_{4}+\mathrm{C}_{2} \mathrm{H}_{4} \mathrm{O}_{2}
$$
What is the theoretical yield (in grams) of aspirin, $\mathrm{C}_{9} \mathrm{H}_{8} \mathrm{O}_{4},$ when $2.00 \mathrm{~g}$ of salicylic acid is heated with $4.00 \mathrm{~g}$ of acetic anhydride? If the actual yield of aspirin is $1.86 \mathrm{~g}$, what is the percentage yield?

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Stoichiometry

Stoichiometry involves using the balanced chemical equation to relate the amounts of reactants and products in a chemical reaction based on mole ratios. It is essential for predicting how much product will form from given quantities of reactants.

Limiting Reactant

The limiting reactant is the substance that is completely consumed first in a chemical reaction, thereby limiting the amount of product that can be formed. Identification of the limiting reactant is crucial for accurate yield calculations.

Molar Mass Calculation

Molar mass calculation is the process of calculating the mass of one mole of a chemical compound by summing the atomic masses of its constituent elements. This conversion between mass and moles is fundamental in stoichiometric computations.

Theoretical Yield

The theoretical yield is the maximum amount of product that can be formed from a given amount of reactant, as predicted by stoichiometry. It assumes that the reaction proceeds perfectly without any losses.

Percent Yield

Percent yield compares the actual amount of product obtained in a reaction to the theoretical yield, expressed as a percentage. This metric is used to assess the efficiency of a chemical reaction.

Transcript

00:02 We are trying to figure out the percent yield that we can gain from the formulation of aspirin.

00:11 So this is the compound for aspirin.

00:13 We're starting off with two grams of c7h603 and four grams of c4h603.

00:21 So let's try to figure out what our theoretical yield is to figure out our percent yield.

00:26 So two grams of this.

00:29 We want to convert this grams to moles, and the way we're going to do that is use our molar mass, which i found out here.

00:41 So we're going to divide 2 by 138 .032 grams, because that's per every one mole.

00:54 So when we do that, two divided by 138 .032, we get 0 .044 moles of c7.

01:11 H603.

01:12 And because all of this is a one -to -one ratio, when we convert moles to moles using a mole ratio, this amount is going to be equivalent to the same amount of aspirin, so 0 .041 -4 moles of aspirin.

01:35 Alright, now we're going to figure out how many moles of aspirin we can create from 4 grams of this starting value, c4h603.

01:45 Do this same thing, divide by the molar mass.

01:48 In this case, it's 102 .032.

01:56 And we do 4 divided by 102 .032, we get 0 .039 moles 392, moles of c4h603.

02:14 And remember that is the same as moles of aspirin.

02:21 So when we're comparing, oh, i see 9, 8803.

02:26 When we're comparing these, we want to look for the lowest amount...

Please give Ace some feedback