Answer : The correct option is, (B) Salicylic acid
Solution :
First we have to calculate the moles of salicylic acid and acetic anhydride.
Now we have to calculate the limiting and excess reagent.
The balanced chemical reaction is,
From the balanced reaction we conclude that
As, 2 moles of salicylic acid react with 1 mole of acetic anhydride
So, 0.507 moles of salicylic acid react with mole of acetic anhydride
The excess of acetic anhydride = 0.783 - 0.2535 = 0.5295 moles
That means the in the given balanced reaction, salicylic acid is a limiting reagent because it limits the formation of products and acetic anhydride is an excess reagent.
Hence, the limiting reagent is, salicylic acid.