lab question on collecting gas and finding it's mmass?

Question

A student performs an experiment to determine the mmass of an unknown gas. A smalll amount of the pure gas is released from a pressurized container and collected in a graduated tube over water at rooom temp. The collection tube containing the gas is allowed to stand for several minutes, and its depth is adjusted until the water levels inside and outside the tube are the same. Explain the purpose of equalizing the water levels inside and outside the gas collection tube.

Answer 1

Adjusting the container ensures that the pressure inside of container (Pgas + vapor pressure of water) is equal to the pressure outside (atmospheric pressure).

Answer 2

To ensure that the gas is at atmospheric pressure.
The pressure outside the tube is at atmospheric, when the level inside is equal to that outside, both pressures are the same.
The gas volume at atmospheric pressure can then be noted.

(You can only find its mass if you have its density).

Answer 3

LOL! there is something very incorrect including your equation. i assume you meant 2H202 ---> 2H20 + O2 considering the fact that 2 moles of hydrogen peroxide produce one mole of O2 all you're able to do is convert the 50.0g to moles, divide it via 2 and that's the moles of O2. Then endure in recommendations what share liters at STP a mole of any gasoline has and you diverse that via the style of moles you have and you have your answer.

Answer 4

To elimante variables in experiments