in a particular experiment, 150.0 g of ammonium chloride were reacted with 290.0 g of barium hydroxide octahydrate, producing 157.2 g of water

1. find the limiting reagent in this situation
2. calculate the theoretical yield of water
3. calculate the percent yield of water
4. what mass of anhydrous barium hydroxide contains the same number of moles of Ba 2+ ions as 31.5 g barium hydroxide octahydrate

Here is a worked example of a limiting reagent problem. This process will work all of your limiting reagent problems.

http://www.jiskha.com/science/chemistry/limiting_reagent_problem.html