A chemistry lab experiment requires 34.0 g of silver nitrate. How many grams of a 23.1% by mass solution of silver nitrate should be used?

Answer 1

23.1% by mass means the solution has 23.1 g AgNO3 per 100 grams of solution.
You want 34.0 g; therefore,
100 g soln x (34.0/23.1) = ?? g soln needed.

You can look at it another way; i.e.,
you want (34.0/x g soln) = 0.231 and solve for x.