Question

a. The common laboratory solvent diethyl ether (ether) is often used to purify substances dissolved in it. The vapor pressure of diethyl ether , CH₃CH₂OCH₂CH₃, is 463.57 mm Hg at 25 °C.

In a laboratory experiment, students synthesized a new compound and found that when 16.70 grams of the compound were dissolved in 168.0 grams of diethyl ether, the vapor pressure of the solution was 454.90 mm Hg. The compound was also found to be nonvolatile and a non-electrolyte.

What is the molecular weight of this compound?

diethyl ether = CH₃CH₂OCH₂CH₃= 74.12 g/mol.


MW =  g/mol

b. The vapor pressure of ethanol is 54.68 mm Hg at 25°C.

How many grams of estrogen (estradiol), C₁₈H₂₄O₂, a nonvolatile, nonelectrolyte (MW = 272.4 g/mol), must be added to 274.9 grams of ethanol to reduce the vapor pressure to 53.60 mm Hg ?

ethanol = CH₃CH₂OH = 46.07 g/mol.

g estrogen

Answer 1

Answer :-

For the first question, to find the molecular weight of the compound first moles of the compound is calculated then molecular weight is calculated. For second question again moles are calculated first, then mass is calculated.

The answer is given in the image,

44.12 , = 2 . 2666,01 0-1813 - 2.2666 2.2242 + o-9813m2-2, 2666

0.981372 0.04 24 "m= 0.0432 mol Molecular mass- mas o 0432 :. 386.gg/mo l Po 54-68 4-6-o7 m2つ0.1205m] =33.069 .