Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

4.500mL of an unknown organic liquid (Specific Gravity=0.785)was placed in a fla

ID: 689545 • Letter: 4

Question

4.500mL of an unknown organic liquid (Specific Gravity=0.785)was placed in a flask and vaporized as in the experiment.Dataobtained follows: weight of vapor: 0.647g temperature of vapor:100 o C volume of vapor:145mL pressure of vapor:765.2 torr a) Using the above data, calculate the experimental molarmass. b)Calculate mL of the liquid that condensed. 4.500mL of an unknown organic liquid (Specific Gravity=0.785)was placed in a flask and vaporized as in the experiment.Dataobtained follows: weight of vapor: 0.647g temperature of vapor:100 o C volume of vapor:145mL pressure of vapor:765.2 torr a) Using the above data, calculate the experimental molarmass. b)Calculate mL of the liquid that condensed.

Explanation / Answer

   a) Unknown organic liquid V = 500mL        Specificgravity          s.g = 0.785      so mass of unknown organicliquid   m = V * s.g                                                            = 500*0.785 g                                                            = 392.5 g       weight of vapour =0.647 g       temperature of vapor:100o C     volume of vapor:145mL     pressure of vapor:765.2 torr       but we know   PV = nRT                                  = (weight /molar mass )*RT                        weight /molar mass = PV /RT                molar mass = (RT /PV)* weight                                                           = [(0.0821lit.atm /mol.K)*(373K) / (1.07 atm*0.145L) ]*0.647g                                    = 127.7 g/mol    molar mass of vapour = 127.7g/mol b) Volume of the liquid condensed V = massof condensed / specific gravity                                                            = (initial mass of liquid - mass of vapour) / specificgravity                                                            = (392.5g -0.647 g) /0.785                                                            = 499 mL      Volume of liquid condensed =499 mL
Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote