Chemistry help - Reacting Masses?

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

Chemistry help - Reacting Masses?
It is basically all about molecular weights.


C5H11NO2 = 117g/mole


KNO2 = 85 g/mole


C5H11OH = 88g/mole


H2SO4 =98 g/mole


H2O = 18g/mole


KHSO4 = 136 g/mole





a) You have to work out the number of moles of each reactant you have.


KNO2 = 14.5g/ 85g/mole = 0.17moles


C5H11OH = 15g/88g/mole = 0.17moles


H2SO4 = 30g / 98 g/mole = 0.30 moles


Sulphuric acid in excess as there are extra moles.





b) As you use 0.17moles of reactants, you get 0.17moles of each of the products.


C5H11NO2 = 0.17 moles = 0.17 * 117g/mole = 19.89 g





c) 12g / 19.89g * 100% = 60% yield