Question

A gas occupies 2.5 L at 750 mm Hg pressure and 25℃. At the same temperature and 500 mm Hg pressure the volume will become

Answer 1

volume will become half

Answer 2

Answer:

3.8L

Explanation:@ 750mm Hg Pressure

Given,

P = 750mm Hg

T = 25°C = 25 + 273.15 = 298.15K

V = 2.5L

R = 0.082 L atm K−1 mol−1.(Gas constant)

n = ?

By using ideal gas Equation,

PV = nRT

750 * 2.5 = n * 0.082 * 298.15

           n = 76.7 = 77 mol.   ---------------------(Equation 1)

Now,

To find the volume @500mm Hg Pressure,

Using the same Ideal gas eqution,we get

PV = nRT

500 * V = 77 * 0.082 * 298.15

         V = 1882.5/500

         V = 3.76 = 3.8L.

So the Volume of the Gas @ 500mm Hg Pressure is 3.8L