An Erlenmeyer flask that weighs 93.667g has a quantity of liquid vaporized in it
ID: 795488 • Letter: A
Question
An Erlenmeyer flask that weighs 93.667g has a quantity of liquid vaporized in it at 96.4oC and a pressure of 1583.8 torr. The mass of the cooled flask is 94.345g. When the flask is filled with water, the mass of the flask and water is 268.92g.
(a). Determine the molecular weight of the unknown liquid. Blank 1 g/mol ** Write answer in decimal form to one decimal place, NO units in answer**
(b). Given the following compounds:
Liquid Molecular Weight (g/mole)
Pentane 72.2
Acetone 58.1
Methanol 32.0
Hexane 86.2
Ethanol 46.1
Propanol 60.1
What is the identity of the unknown liquid? Blank 2
Explanation / Answer
The question is not scientific as it measures weight with a unit of mass.
Mass of water filling the flask =268.92 g - 93.667 g = 175.25 g
(a)Volume of the flask = 175.25 g / (1.00 g/cm^3) = 284.4 cm^3
(b) flask mass when filled with chloroform = 93.667 g + 284.4 cm^3 * 1.48 g/cm^3 =514.57g