At 300 K , an ideal dilute solution of a macromolecule exerts osmotic pressure that is expressed in terms of the height ( h ) of the solution (density =1.00 ~g ~cm ⁻³ ) where h is equal to 2.00 cm . If the concentration of the dilute solution of the macromolecule is 2.00 ~g dm ⁻³ , the molar mass of the macromolecule is calculated to be X 10^4 ~g ~mol ⁻¹ . The value of X is . Use : Universal gas constant ( R )=8.3 ~J