Question

All of the following containers have the same volume and temperature, which container has the most molecules

Answer 1

The question is incomplete. Complete question is:
All of the following containers have the same volume and temperature, which container has the most molecules
container 1-25.0 atm
container 2-50.0 atm
container 3- 12.5 atm
container 4- 1.00 atm
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From, ideal gas equation, we know that PV = nRT

Thus, number of moles of gas depends on pressure, volume and temperature. Since, volume and temperature are held constant. number of moles of molecules will depends only on pressure of gas.

From above equation is can be seen that n α P. Thus higher the pressure, more will be the molecules. 

∴ In present case, container 2 will have most molecules, as it has maximum pressure.