Disclosure: This web page might contain affiliate links that earn this website a little commission, at no expense to you.

You are watching: Calculate the percent yield of asa synthesized in part a.

The post-lab questions provided are SIMILAR to concerns you might enrespond to in your lab manual. These concerns will provide you via a step-by-action guide on exactly how we approached the trouble. You deserve to use this overview and the information you taped to assist answer the questions. Any offered examples via worths will be through mock worths. Use of these worths will virtually assuredly give you nonsensical calculations. They are just expected to highlight the logic.

### question 1

You are asked to calculate the percent yield of aspirin, give what the value must be (theoretical yield), and also describe why your worth (actual yield) might vary from this

From the above reaction we recognize the amount of salicylic acid is a 1 to 1 (1:1) proportion via the amount of aspirin. This implies eexceptionally mole of salicylic acid supplied will certainly yield the same variety of moles of aspirin. Thus, the first step is to calculate the variety of moles of salicylic acid used. Note: you are told that acetic anyhydride is in excess and also salicylic acid is the limiting reagent

Mass of Salicylic Acid Used (mock value) = 276.24 g

Molar Mass of Salicylic Acid = 138.12 g

Moles of Salicylic Acid = (1)/(2) = 276.24/138.12 = 2.000 moles

To then convert the number moles of Aspirin to the meant yield in grams, we multiply the moles by the molar mass of asprin

Moles of Salicylic Acid = Moles of Aspirin —> 2 moles of Salicylic Acid renders 2 moles of Asprin

Molar Mass of Aspirin = 180.16 g

Theoretical yield of Aspirin (g) = (2 moles)(molar mass of aspirin) = 2.000(180.16) = 360.3 grams

Percent Yield Calculation (remember considerable figures)

Your actual yield will be the amount aspirin you weighed after it was filtered and dried in lab. Using the theoretical and actual you can calculate percent yield.

Actual Yield of Aspirin in lab after filtered/dried (mock value) = 370 g

Mass of Theoretical Yield of Aspirin (mock value) = 360.3 g

Percent Yield = (Actual ÷ Theoretical) x 100 = (370 ÷ 360.3) x 100 = 103 %

Your value might vary from the theoretical worth for a number of factors. If it is over 100%, it might be bereason your aspirin was not entirely dried. If it is below 100%, it might be bereason of sample loss once moving to the weigh paper.

### Concern 2

Asks you between aspirin and also salicylic acid, which reacts through FeCl3FeCl3 only reacts with copounds that have phenols. Determine whether aspirin or salicylic acid has actually a phenol and also that need to be the one that reacts with FeCl3

View fullsize

Phenols (click to enlarge)

### Inquiry 3

Asks you to find 3 prevalent esters and attract the structures.