Reacting Masses - Help!?

Managed the rest of the sheet I was given, but this question has completely stumped me - any help would be much appreciated :)





"Amyl nitrate (C5H11NO2) is a vasodilator. A research student found a method for making this compound on the internet. Some of the details were downloaded and are given below.





Dissolve 14.5g of potassium nitrate (KNO2) in 8ml of water and in a separate vessel mix 15g(18ml) of amyl alcohol C5H11OH with 30g of concentrated sulphuric acid. Cool the latter and add it slowly to the solution of the nitrite with stirring.





C5H11OH + KNO2 + H2SO4 --%26gt; C5H11NO2 + H2O + KHSO4





a) Which reactant or reactants is or are in excess?


b) If the student used the method above, calculate the maximum amount of amyl nitrite formed. Assume the reaction goes to completion.


c) The student successfully followed the method above and managed to make 12g of the product. Calculate the percentage yeild of amyl nitrite obtained in the preparation."





Thanks

Reacting Masses - Help!?
a) Reactants in excess: Sulfuric acid and KNO2





b) Limiting reagent: Amyl alcohol


Max amount of amyl nitrate formed


= 15 / 88 x (60 + 11 + 14 + 32)


= 19.94318181


= 20 g (2 significant figures)





c) 12 / 20 x 100%


60%