Question

Aspirin (C9H8O4) is synthesized by reacting salicylic acid (C7H6O3) with acetic anhydride (C4H6O3) according to the reaction: C7H6O3 + C4H6O3 --> C9H8O4 + HC2H3O2 a. What mass of acetic anhydride is needed to completely react 1.00 x 10 4 g of salicylic acid?

Answer 1

`7.39* 10^(3)g` of acetic anhydride is needed

Step-by-step explanation:

According to balanced equation, 1 mol of salicylic acid completely reacts with 1 mol of acetic anhydride

Number of moles = (mass)/(molar mass)

Molar mass of acetic anhydride = 102.09 g/mol

Molar mass of salicylic acid = 138.121 g/mol

So,
`1.00* 10^(4)g` of salicylic acid =
`(1.00* 10^(4))/(138.121)moles` of salicylic acid

Hence,
`(1.00* 10^(4))/(138.121)moles` of salicylic acid reacts completely with
`(1.00* 10^(4))/(138.121)moles` of acetic anhydride.

So, mass of acetic anhydride needed =
`(1.00* 10^(4))/(138.121)* 102.09g` =
`7.39* 10^(3)g`