I really really need some help with this percent yield problem? General Chemistry?

Question

Silver is reacted with excess mercury (II) chloride, producing a solid silver chloride precipitate. If the actual yield of 25.5 g silver chloride represents a 77% yield, how much silver was initially present?

Ag (s) + HgCl2 (aq) ------> AgCl (s) + Hg (l)

I already balanced the equation:

2 Ag + HgCl2 -------> 2 AgCl + Hg

I am just so confused on how to solve this!
What I know for sure is that the percent yield is actual yield/theoretical yield * (100), but I am not sure if that formula even matters in this question. I would love to learn though!
Thank you for your help!

Answer 1

You can solve this problem by determining the mass of silver in 25.5 grams of silver chloride, then multiply by the factor which accounts for the yield:

 

g Ag = 25.5 g AgCl (107.8682 g Ag / 143.3212 g AgCl) (100/77) = 24.92 g