A student obtains a yield of 79% from his salicylic acid. How many grams of salicylic acid will the student need to produce 135 g of aspirin?
Ask yourself,
79% of what = 135 or
0.79*x = 135, then
135/0.79 = x
okay so what that guy said is right but here is the whole thing
135g / 0.79 = 170.886 g of SA (salicylic acid)
my chem teacher told me i did it right soooo
To find out how many grams of salicylic acid the student will need to produce 135 g of aspirin, we can use the concept of a yield. The yield is the amount of product obtained in a reaction relative to the theoretical amount that could be obtained.
In this case, the student obtained a yield of 79%. This means that if the student obtained 79% of the theoretical yield, the remaining 21% was lost during the reaction or purification process.
To calculate the theoretical yield, we need to assume that the reaction goes to completion and that the student achieves a 100% yield. We can set up a proportion to find the amount of salicylic acid needed:
(Theoretical Yield)/(Amount of Salicylic Acid) = (Actual Yield)/(Amount of Aspirin)
Since the student obtained a yield of 79%, the actual yield is 79% of the theoretical yield. Let's assume the amount of salicylic acid needed is x grams.
(100%)/(x g) = (79%)/(135 g)
To solve for x, we can cross multiply and then divide:
(79%)(x g) = (100%)(135 g)
0.79x g = 135 g
Dividing both sides by 0.79:
x g = 135 g / 0.79 ≈ 171.52 g
So, the student will need approximately 171.52 grams of salicylic acid to produce 135 g of aspirin, assuming a 79% yield.