Question

The cylinder in the drawing contains 3.81 mol of an ideal gas. By moving the piston, the volume of the gas is reduced to one-fourth its initial value, while the temperature is held constant. How many moles Δn of the gas must be allowed to escape through the valve, so that the pressure of the gas does not change?

Answer 1

its 3/4 of the original mol
(3/4) * 3.81= 2.8575