# chemistry

Here is the question:

A sample of an unknown volatile liquid was injected into a Dumas flask (mflask=27.0928g. Vflask=.104L) and heated until no visible traces of the liquid could be found. The flask and its contents were then rapidly cooled and reweighed (mflask+vapor=27.4593g) The atmospheric pressure and temperature during the experiment were 0.976 atm and 18.0 °C, respectively. The unknown volatile liquid's molecular mass was __________.

I have not got any concrete homework done on this outside of guessing and checking can someone set up this equation for me or explain how this can be done?

1. 👍 0
2. 👎 0
3. 👁 1,577
1. Use n = PV/RT to get the number of moles in sample used.

Divide the grams of sample used by the number of moles to get the grams/mole which is the same as the molar mass. That is numerically the same as the molar mass.

1. 👍 0
2. 👎 2
2. Thank you that was exactly what I was looking for.

1. 👍 0
2. 👎 0

## Similar Questions

1. ### chemistry

An ideal liquid solution has two volatile components. In the vapor in equilibrium with the solution, the mole fractions of the components are (a) both 0.50; (b) equal, but not necessarily 0.50; (c) not very likely to be equal; (d)

2. ### Physics - Buoyant Force

A piece of metal weighs 50.0 N in air, 36.0 N in water, an 41.0 N in an unknown liquid. Find the density of the unknown liquid.

3. ### chemistry

what is the density of an 84.7g sample of an unknown substance if the sample occupies 49.6cm3? what volume would be occupied by 7.75g of this same substance? PLEASE help need the answer tonight i have a test tomorrow i kind of not

4. ### Physics Fluids

A column of oil of height 70.0 cm supports a column of an unknown liquid. Assume that both liquids are at rest and that the density of the oil is 840 kg/m^3. Determine the density of the unknown liquid.

1. ### Sample purity

Question: A student spots an unknown sample on a TLC plate and develops it in pentane solvent. Only one spot, for which the Rf value is 0.05, is observed. Is the unknown a pure compound? What can be done to verify the purity of

2. ### Chemistry

An Ap student got a lab report back with "-4.5 % error" written in red on it. He had found the boiling point of an unknown liquid to be 45 C. What is the correct boiling point of his unknown liquid? I know first I would write -4.5

3. ### chemistry

A student measure 9.43 mL of an unknown liquid in a graduated cylinder. The mass of the empty cylinder is 34.670 g, and the mass of the cylinder and liquid is 44.197 g. What is the density of the unknown liquid? (remember

4. ### chemistry 101

I have a question that I am not sure how to even start. A 15.0 g sample of a liquied has a density of 0.875 g/ml a what is the voulme in milliters of the liquid? use conversion factors to calculate answer b. What mass, in grams of

1. ### physics

A column of water of height h1 = 70.0 cm supports a column of an unknown liquid h2 = 30.0 as suggested in the figure (not drawn to scale). Assume that both liquids are at rest and that the density of water is 1.0x103 kg/m3.

2. ### Physics

A 500-mL beaker has a mass of 250 g when empty and 645 g when filled with an unknown liquid. What is the density of the liquid?

3. ### Chemistry

three separate questions 1. An empty graduated cylinder weighs 82.450 g. When filled to 50.0 mL, with an unknown liquid it weighs 110.810 g. What is the density of the unknown liquid? 2. It is valuable to know that 1 milliliter

4. ### Science

"A student mixed two clear liquids together in a beaker. A solid and new liquid formed. The student forgot to write down the mass of one of the reactants. The rest of the data is shown in the table below." The data (mass, in