Question

1.)How many grams would you need of a sample known to be 99.81% AgN03 by mass?

You are asked to prepare 150.0 mL of 3.15×10−2 M AgNO3.

2.) An aqueous solution is 6.40% methanol CH3OH by mass, with d = 0.988 g/mL}

What is the molarity of CH3OHOH} in this solution?

Answer 1

M = moles/L
You know M and L, calculate moles.
Then moles = g/molar mass. You know moles and molar mass, calculate g AgNO3 (theoretical AgNO3) but since it isn't 100%, you must correct for that.
grams to weigh *0.9981 = theoretical AgNO3. Solve for grams to weigh.

Answer 2

thank you