3:12 &KPost-laboratory Qu...POST-LABORATORY QUESTIONSDue after Laboratory Experiment1. While performing the Dumas experiment, if the outside of the flask were notcompletely dry (Part I), how would this affect the calculated molar mass of theunknown volatile liquid? Would it be higher or lower? Explain.2. While determining the pressure during the Dumas experiment, if the barometricpressure reported were lower than the actual vapor pressure (Part 1), how would thiserror affect the calculated molar mass of the unknown volatile liquid? Explain.3. While determining the volume during this experiment (Part II), if the total volume ofthe flask were incorrectly reported as 125 mL, how would this error affect thecalculated molar mass of the unknown volatile liquid? Explain.4. Calculate the number of moles of Argon gas contained in a 4.00 dm³ container at 620.kPa and 25.0°C. If the gas is Helium instead of Argon, will the answer change? Explain5. In the Dumas method for determining the molar mass of an unknown volatile liquid,a sample of a volatile liquid that boils below 100°C is vaporized in a boiling water batand the mass of the vapor required to fill the flask is determined. The following datawas collected:6.Flask VolumeMass of Flask + CapMass of Flask + Condensed LiquidMass of Condensed LiquidTemperature of Water Bath (°C)Barometric Pressure (atm).100.0 100.0 +79.6 mL = 279.6 ml143.85 g144.95 g1.10 g84.1 °C0.985 atma. What is the molar mass of the unknown?b. What will its temperature be when the pressure is 1.20 atm and the volume is250.0 mL?HEmical analysis of an unknown compound shows that it contains 64.9% C, 13.5%and 21.6% 0 by mass. At 120°C a 50 mmHg, 2.00 L of the gaseous compoundweighs 4.60 g.

Since you have asked multiple questions, we will solve the first one for you. For remaining…

1. While performing the Dumas experiment, if the outside of the flask were not completely dry (Part I), how would this affect the calculated molar mass of the unknown volatile liquid? Would it be higher or lower? Explain.

1. While performing the Dumas experiment, if the outside of the flask were not completely dry (Part I), how would this affect the calculated molar mass of the unknown volatile liquid? Would it be higher or lower? Explain.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

See similar textbooks

Similar questions

Show complete solutions and enclose all final answers in a box. Round off final answers to 4 decimal places and use floating values for intermediate answers. A gas column is separated into two segments by a non-permeable partition. On the first segment is 1.63 moles of Helium with volume V1 and on the second segment is 3.84 moles of Oxygen gas with volume V2. Consider both gases to be ideal and at the same pressure P and temperature T. If the partition is removed, calculate the change in entropy of the gaseous system.
1. Determine the value of the ideal gas constant.2. Compare your value of ideal gas constant to the literature value, and calculate the percent error. Mg(s) + 2 HCl(aq) -> H2 (g) + MgCl2(aq) given: Mass of Mg Ribbon: 0.0325g10 mL of 6 M HCl Barometric Pressure: 101.8 kPa Room Temperature: 24.5 oC Water Vapour Pressure: 23.1 mmHg Mass of Mg Ribbon: 0.0325g Initial volume of the Burette: 1.55 mL Final Volume of the Burette: 36.35 mL Height of the Water Column in the Burette: 167.0 mm
(This question and the next 2 questions are breakdowns of the same question) A student John wanted to measure the molar mass of an unknown material (UM) via the boiling point change of a solvent. He chose a solvent, ethanol, that can dissolve the material and sugar. He wanted to use sugar (MW = 342.3 g/mol) as a reference sample to get an ebullioscopic constant for his system to reduce the effect of other measuring errors such as pressure, measuring errors, and impurity of the samples. He made 10 solutions each contain 100 g of ethanol and various amont of solute as list in the table. He fits the two sets of data and obtain the molar weight of the unknown materials. For this question answer the fitted boiling point of pure ethanol: ____ K. 4 sig. fig. Thre rest ? marks in the tale will be answered in the next two questions. Copy the data into Excel and use trendline to fit or calculate the average values for this and the next 2 questions. Sample # Sugar (g) B.P. (K) Sample # UM…
The pressure exerted on the gas entrapped in the syringe is proportional to the total mass on the platform. Make two plots. (i) Vol/mL vs. Total mass/g (ii) Vol/mL vs. 1/(total mass/g) If warranted, obtain a trendline and trendline equation. Comments in the results. Is Boyles Law obeyed? Explain.
Determine the mole fraction and partial pressure for each gas in the mixtures below.a) 1.62 g CO2 and 13.5 g XeF2 at STP.b) 679 mg He and 1.21 g NO2 in an 875-mL vessel at 26.3°C.
In a 15-cm. evaporating dish is placed 15.4 g. (0.10 mole) of finely powdered biphenyl (Note 1). The dish is set on a porcelain rack in a 30-cm. desiccator with a 10-cm. evaporating dish under the rack containing 39 g. (12 ml., 0.24 mole) of bromine. The desiccator is closed, but a very small opening is provided for the escape of hydrogen bromide (Note 2). The biphenyl is left in contact with the bromine vapor for 8 hours (or overnight). The orange solid is then removed from the desiccator and allowed to stand in the air under a hood for at least 4 hours (Note 3). At this point, the product weighs about 30 g. and has a melting point in the neighborhood of 152°. The crude 4,4'-dibromobiphenyl is dissolved in 75 ml. of benzene, filtered, and cooled to 15°. The resulting crystals are filtered, giving a yield of 23.4– 24.0 g. (75–77%) of 4,4'-dibromobiphenyl, m.p. 162–163° (Note 4). How large of a scale can this reaction be run safely? Is it expensive?
ITEMS USED FOR EXPERIMENT: •Ring stand •Hot plate •125 mL Erlenmeyer flask•400 mL beaker•10 mL graduated cylinder •Aluminum foil•Rubberband•Paper Clip•Thermometer•Vial containing unknown liquid You know have the following data: Mass of flask + foil + rubberband: 78.637 gMass of flask + foil and rubberband+ unknown condensed liquid: 78.847 gTemperature of water bath: 100C = 373 KPressure of gas in our system: 29.02 inHg = 0.9699 atmVolume of gas in our system: 141 mL = 0.141 L 1. During the experiment, you collect the following data: Mass of flask: 80.001 g Mass of flask + unknown condensed liquid: 80.452 g Temperature of water bath: 100 °C Pressure of gas in our system: 0.998 atm Volume of gas in our system: 265 mL Which of the following number(s) need a conversion before they can be used? (Check all that apply) [ ] Group of answer choices [ ] Volume of gas in our system [ ] Mass of flask [ ] Temperature of water bath [ ] Pressure of gas in our system [ ] Mass of flask +…
In an experiment carried out at a temperature of 4700C and a pressure of 100 atmosphere, 4.3g of a volatile liquid produced 30.6cm3of the gas. Calculate the molar mass of the liquid. (Molar gas constant, R= 8.314JKmol, molar gas volume at stp = 22400cm3, 1 atmosphere= 1.0 x 10 Nm-2)
A student performed the experiment described in this module, using 7.00 mL of a 1.8% H2O2 solution with a density of 1.01 g mL-1. The water temperature was 20 ° C, and the barometric pressure in the laboratory was 30.02 in. Hg. After the student immersed the yeast in the peroxide solution, she collected 45.1 mL of O2. (11) Calculate the percent error for the experiment. What is the observed molar volume?
Forgot to put the units they are asking for on the previous submission. Am I doing this correctly? A gaseous sample of molecules, with a molar mass of 87.9 g/mol, is contained in a cylinder at a temperature of 362. K and pressure of 101.9 kPa. The collision cross section of a molecule is 0.73 nm2 The collision freqency, z, of the gas under these conditions is ____________ s-1.
Calculate the values of vrms, vmp, and vmean for Cl2 (70.90 g mol-1) at 25 °C
solve as neatly as possible and show completesolution. Round your final answer to 4 decimal places and box / highlight all final answers. and all values must include proper units with proper conversion if needed in your solution. kindly folllow the format Given,Required,Solution subject physical chemistry 1. Calculate the mass of water vapor present in a room of volume 400 m3 thatcontains air at 290C when the relative humidity is 53.0%. Compute for the vaporpressure of water?