Solute ' X^ dimerises in water to the extent of 80 % .2 .5 ~g of ' X^ in 100 ~g of water increases the boiling point by 0.3^ C . The molar mass of ' X^ is [K_ b =0.52 ~K ~kg ~mol ⁻¹ ]

Step-by-step solution

Here, 2.5 ~g X in 100 ~g water is increasing boiling point by 0.3^ C and X is getting dimerise to the extent of 80 % . Molar mass of X= ? K_ b =0.52 Here, i= 1- + 2 1 =1-0.8+ 0.8 2 (Due to 80 % dimerisation) i=0.6 Now, M=K_ b ( w_ B 1000 w_ A T_ b ) i aligned &=0.52 ( 2.5 1000 100 0.3 )= 52 100 25 3 10 0.6 &=26 aligned