CHE 110L Lecture Notes - Lecture 3: Dumas Method, Ideal Gas Law, Alcohol Thermometer

• School: Quinnipiac University
• Department: Chemistry
• Course: CHE 110L
• Professor: Stephen Madison

Document Summary

Gas law experiment: determination of the molar mass of a volatile liquid. The purpose of this lab was to use the ideal gas law and its properties of gases to determine the molecular weight of a volatile liquid using the dumas" method. The procedure for this lab can be found on pages 65-67 in general chemistry che110l. Carbon copies of data tables have been attached to the back of this lab report. Trial 1: 101 + 273 = 374 k. Trial 3: 100 + 273 = 373 k: # mol unknown. Trial 1: n=[(1 atm)(0. 283 l)]/[(0. 0821 l-atm/mol-k)(374 k)]=0. 00922 mol. Trial 2: n=[(1 atm)(0. 283 l)]/[(0. 0821 l-atm/mol-k)(373 k)]=0. 00924 mol. Trial 3: n=[(1 atm)(0. 283 l)]/[(0. 0821 l-atm/mol-k)(373 k)]=0. 00924 mol: molar mass. Mm=[(0. 516 g)(0. 0821 l-atm/mol-k)(374 k)]/[(1 atm)(0. 283 l)]= 56. 0 g/mol. Mm=[(0. 516 g)(0. 0821 l-atm/mol-k)(373 k)]/[(1 atm)(0. 283 l)]= 55. 8 g/mol. Mm=[(0. 570 g)(0. 0821 l-atm/mol-k)(373 k)]/[(1 atm)(0. 283 l)]= 61. 7 g/mol: average molar mass & deviation. 56. 0 g/mol + 55. 8 g/mol + 61. 7 g/mol = 57. 8 g/mol.