Determine the mass of AgNO3?

Question

Determine the mass of AgNO3 (MW = 170g/mol) required to dissolve in 400 mL solution in order to prepare a solution which is .14 M AgNO3

Answer 1

Molarity = moles / V (in L)

0.14 = moles / 0.400 L

moles = 0.14 x 0.400 = 0.056

Mass AgNO3 = 0.056 mol x 170 g/mol =9.5 g ( 2 significant figures)

Answer 2

Molarity = moles / L

0.14 = moles / 0.400 L

moles AgNO3 = 0.14 x 0.400 = 0.056 moles

0.056 moles AgNO3 x (170 g AgNO3 / 1 mole AgNO3) = 9.5 g AgNO3

Answer 3

1M AgNO3 solution = 170g in 1 liter = 0.4 x 170g in 400 ml = 68g/400 ml

0.14M AgNO3 = 68 x 0.14 g in 400 ml = 9.52g/400ml

Answer 4

M=a/(V*A)

M=.14 M V=400 mL =.4 L (volume must be taken in liters)

A=170

.14=a/(.4*170)

so, a=.14*.4*170=9.52 g