Tuesday, May 17, 2011


22. Limiting Reactants
a) If 8.6L of H2 reacted with 4.3L of O2 at STP, what volume of excess reactant will remain after the reaction is complete? (reaction on review packet)

First, figure out the limiting reactant

As you can see, both of the reactants equal the exact same number of moles, .38. In this case both reactants are adequate, and neither elements needs the other to react. There is no excess. 

b) If a total of 1134g of NaHCO3 and 864.0g of C6H8O7 react, how many moles of CO2 and Na3C6H5O7 will be produced? 

First, find the moles of the limiting reactant in terms of CO2

As you can see, NaHCO3 is the limiting reactant. now use 13.50 moles and convert it to NaC6H5O7

13.50 mol CO2, 4.500 mol Na3C6H5O7


  1. Both part A and part B look great. I can't find any mistakes. This truly helps.

  2. Hey, I could definitely be wrong, but I am getting 13.49 mol CO2 for the C6H8O7 conversion... I used the same conversion factors too.

  3. I am getting the same thing as eric. But i don't know if that would mean the answer is no excess too, or if you would use 13.49 since its just .01 smaller?