Question

APPLICATION OF KINETIC MOLECULAR THEORY

you are holding two balloons of the same volume. one contains helium and the other one contains hydrogen.what would be the relationship of their pressure? different or same?

Answer 1

The higher the molecular mass, the higher the density. The higher the density, the higher the pressure.
Hydrogen-1.0079
Helium- 4.0026

Helium has more pressure.

Answer 2

Pressure is not dependent on density, but the number of moles ONLY. Assuming both of these samples are at the same temperature, their average kinetic energies are equal, and thus their pressures are the SAME.

Answer 3

the kinetic molecular theory is a model which is NOT PERFECT!! these are its postulates:

Postulates

A gas consists of a collection of small particles traveling in straight-line motion and obeying Newton's Laws.

The molecules in a gas occupy no volume (that is, they are points).

Collisions between molecules are perfectly elastic (that is, no energy is gained or lost during the collision).

There are no attractive or repulsive forces between the molecules.

The average kinetic energy of a molecule is 3kT/2. (T is the absolute temperature and k is the Boltzmann constant.)



Ofcourse these postulates aren't 100% true but they stil describe the behaviour very precisive!!
So because the molecules in a gas are considered as points and that it is also considered that there is no interaction between the gasses you can say the relation of the pressure to this particular question is the same for helium and hydrogen. That is ofcourse considered within the kinetic molecular theory.

Answer 4

the helium balloon would weigh more, but assuming that the balloons are at the same temperature (since you are holding both of them this is a reasonable assumption), then @dominusscholae is correct. The pressure of each balloon is the same. It is also going to be (roughly) equal to the pressure outside the balloons provided by the atmosphere.

Answer 5

\[PV = nRT\]
\[P = \frac{1}{V} nRT\]
Given that the volume is the same, and I assume the temperature.
P depends only n, but n isn't given.