# A current of dry air was bubbled through a bulb containing 26.66 g of an organic substance in 200 g of water, then through a bulb at the same temperature containing pure water and finally through a tube containing fused calcium chloride. The loss in weight of water bulb is 0.0870 g and gains in weight of $CaCl_2$ tube is 2.036 gm. Calculate the molecular weight of the organic substance in the solution.

63.59
Hence (A) is the correct answer.