The pressure, P, of a gas varies inversely with its volume, V. Pressure is measured in units of Pa. Suppose that a particular amount of a gas is initially at a pressure of 104 Pa at a volume of 108 L. If the volume is expanded to 432 L, what will the new pressure be?

26 Pa

27 Pa

416 Pa

1728 Pa

The answer is 26 Pa.

The ideal gas law can be presented as:

PV = nRT

where

P - pressure of the gas,

V - volume of the gas,

n - amount of substance of gas,

R - gas constant,

T - temperature of the gas.

But, we do not need to know all of the equation members since the right side of the equation is not affected and will remain the same. It is enough the left side of the equation:

P₁V₁ = P₂V₂

It is given:

P₁ = 104 Pa

V₁ = 108 L

V₂. = 432 L

The unknown is P₂ = ?

P₁V₁ = P₂V₂.

104 Pa * 108 L = P₂ * 432 L

11,232 Pa L = P₂ * 432 L

P₂ = 11,232 Pa : 432

P₂ = 26 Pa

Therefore, the new pressure will be 26 Pa.