gas pressure volume

Question

A sample of gas at constant volume and constant number of moles was cooled from 400 K to 200 K. If its initial pressure was 3.50 atm, what was its final pressure? (answer in mmHg)

Answer 1

Hey Lindsey,

 

P₁       P₂

---  =   ---

T₁       T₂

 

Gay-Lussac's Law: The Pressure Temperature Law

 

As the temperature increases, the molecules in the gas move faster, impacting the gas’s container more frequently and exerting a greater force. This increases the pressure.

 

T is in Kelvin and P is in atm or mmHg.

 

3.50/400   =   P₂/200   

 

P₂ = 1.75 atm   (3 - sig figs) 

 

760 mmHg = 1 atm

 

760 x 1.75 = 1330

 

P₂ = 1330 atm

 

Good luck to you.