A reaction of 48.5 g of Na and 53.7 g of Br2 yields 55.4 g of NaBr. What is the percent yield?
2Na+Br2 2NaBr
This is another LR problem. So go through the math as in the last problem and the grams of product formed is what you get for 100% yield. That is called the theoretical yield (TY). The problem tells you what the actual yield (AY) is.
Then % yield = (AY/TY)*100 = ?
Post your work if you get stuck.