Consider the equation for calculating molarity: (no. of mole of solute)÷(volume of solution)
First, let's find the no. of mole of solute in AgNO3. As (no. of mole) = mass / molar mass
no. of mole of 85.0g of AgNO3 = 85.0/(107.9+14.0+16.0x3)
=0.5mol
Since the volume of the solution has to be in dm3, just divide the volume in cm3 by 1000 to get the volume in dm3.
Volume of solution = 500/1000
= 0.5 dm3
Therefore, the molarity is
0.5/0.5
=1.0M
The answer should be B.
