Question

How many grams of AgNO3 are needed to prepare a 0.25 m solution in 500 grams of water?
Question 2 options:


125 g


0.125g


21.25 g


170g

Answer 1

Volume = V = 250ml = 0.25 L 
M = 0.135M 
Molar mass of AgNO3 = 108+14+3*16 = 170 

M = mole/V 
mole = 0.135*0.25 = 0.03375 mole 

mole = mass/molar mass 

mass = 0.03375 * 170 = 5.7375 gr