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

Answer:

$7.39\times 10^{3}g$ of acetic anhydride is needed

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, $1.00\times 10^{4}g$ of salicylic acid = $\frac{1.00\times 10^{4}}{138.121}moles$ of salicylic acid

Hence, $\frac{1.00\times 10^{4}}{138.121}moles$ of salicylic acid reacts completely with $\frac{1.00\times 10^{4}}{138.121}moles$ of acetic anhydride.

So, mass of acetic anhydride needed = $\frac{1.00\times 10^{4}}{138.121}\times 102.09g$ = $7.39\times 10^{3}g$