What mass of sucrose ({\rm{C}}_{12}{\rm{H}}_{22}{\rm{O}}_{11}) should be combined with 497 {\rm g} of water to make a solution with an osmotic

What mass of sucrose ({rm{C}}_{12}{rm{H}}_{22}{rm{O}}_{11}) should be combined with 497 {rm g} of water to make a solution with an osmotic pressure of 8.20 {rm atm} at 320 {rm K}? (Assume the density of the solution to be equal to the density of the solvent.)