Question

A 1.50 liter sample of dry air in a cylinder exerts a pressure of 3.00 atmospheres at a temperature of 25oC. Without change in temperature, a piston is moved in the cylinder until the pressure in the cylinder is reduced to 1.00 atmosphere. The volume of the gas is:

Answer 1

At constant temperature, volume and pressure of a gas may be considered inversely proportional. This is pV = constant.

Then, 3.00 atm * 1.5 liter = 1atm*V

Solve for V, to obtain V = 3atm*1.5liter / 1atm = 4.5 liter

Answer: 4.5 liter

Answer 2

The answer is 4.5 l

To calculate this, we will use the Boyle's law using constant k, pressure P, and volume V:

 PV = k

We can forget temperature since it is constant.

We have:

P1V1 = k

P2V2 = k

So, P1V1 = P2V2

P1 = 3 atm

V1 = 1.5 l

P2 = 1 atm

V2 = ?

_____

P1V1 = P2V2

3 atm * 1.5 l = 1 atm * V2

4.5 atm/l = 1 atm * V2

V2 = 4.5 atm l / 1 atm

V2 = 4.5 l