Question

3. Reserpine, a non-electrolyte, is a natural product isolated from the roots of the shrub Rauwolfia serpential. Nobel Prize winner R.B. Woodward first synthesized it in 1956. Reserpine is used as a tranquilizer or as a sedative. When 1.00 grams of reserpine is dissolved in 25.0 grams of camphor, the freezing point of the solution is lowered by 2.63 oC. The kf for camphor is 40.00 oC kg/mol.

a. What is the molecular mass of reserpine?

b. Determine the molecular formula of reserpine, given that its empirical formula is C33H40N2O9.

Answer 1

Answer :-

Firstly molality of the solution is calculated, from the formula of depression in freezing point then from the formula of molality, molar mass is calculated and thwn molecular formula.

The answer is given in the image,

Aгцшаs 4Ty 2.63 c 40-00c/mol Аg-Kfm а ТЕ 2-63 — о.06SSm Ao.o я. оо[Хио -u weleularmars massy seluentty) О -о6StS 1о x1000 mobeulanmalя250 molaaular maks = 608-4gnol emoleeudco mar of fuspmeо0.4а/ В Empsical jola - C33H4oNyOg Empi ced me- 3302+40х1+2x14+9x/6 608 дmol. Se moleculan mан - Empie'Cad таy Moleculan jormula= Emp&iel tormde - Сз3 Ифом0я