Chem review question help!?

A lithium salt used in lubricating grease has a formula LiC(n)H(2n+1)O2. the salt is soluble in h2o to the xtent of 0.036g per 100g h2o at 25degreeC. the osmotic pressure of dis soln. is found to be 57.1 torr. uming dat molalilty and molarity in such a dilute soln are the same and dat d lithium salt is completely dissociated in the soln, determine an appropriate value of n for the formula for the salt.