Report all results to the correct number of significant figures. An empty flask
ID: 529651 • Letter: R
Question
Report all results to the correct number of significant figures. An empty flask weighs 127.038 g. After vaporization of a sample of volatile liquid as described in the experimental write-up, at a measured temperature of 99.8 degree C, the flask is sealed, cooled to room temperature, and weighed. The mass is now 127.405 g. The measured P_atm is 759.1 torr. The flask is rinsed and filled completely with water at 21.8 degree C. The mass of the flask is now 376.136 g. Calculate the volume of the flask from the mass of water contained in the flask and the density. Calculate the molar mass of the volatile liquid.Explanation / Answer
From the data
1. Volume of flask = 376.136 - 127.038
= 249.098 g/1 g/ml [density = 1 g/ml]
= 249.098 ml
= 0.249098 L
2. mass of volatile liquid = 127.405 - 127.038 = 0.367 g
molar mass of volatile liquid = 0.367 x 0.08205 x (273 + 99.8)/(759.1/760)(0.249098)
= 45.12 mol/g