I just went and did the equation the way I think it goes. Please tell me if I am right:
(1*2.3L)/308.15=(Pf*4.5L)/315.15
so take 4.5L-2.3L=2.2L
then 2.3L/308.15(k)=(2.2*4.5L)/315.15(k)
2.3/308.15=9.9/315.15
final answer is
Pf=2.2
Did I do that right?
Suppose that 2.3 L of gas at 35°C and 1.0 atm is expanded to 4.5 L at 42°C. What will the final pressure of the gas be?
(Ti in Kelvins=308.15; Tf(K)=315.15)
Can someone please show me how to plug the values into the Combined Gas Law formula to calculate for Pf? Please don't perform any calculations. I want to figure it out by myself as I have many practice problems like it.
3 answers
The set up is right. The algebra is not.
(1*2.3L)/308.15=(Pf*4.5L)/315.15
OK for set up You "cross multiply".
1*2.3*315.15 = Pf*4.5*308.15
Pf = 1*2.3*315.15/4.5*308.15
Pf = ?
(1*2.3L)/308.15=(Pf*4.5L)/315.15
OK for set up You "cross multiply".
1*2.3*315.15 = Pf*4.5*308.15
Pf = 1*2.3*315.15/4.5*308.15
Pf = ?
so then:
1*2.3*315.15/Pf*4.5*308.15
Pf=2.38315.15/4.5*308.15
724.85/1386.68
Pf=0.52
ok, great! Thank you very much. I was adding an extra step by subtracting 2.3 from 4.5 and I have no idea why I did that.
1*2.3*315.15/Pf*4.5*308.15
Pf=2.38315.15/4.5*308.15
724.85/1386.68
Pf=0.52
ok, great! Thank you very much. I was adding an extra step by subtracting 2.3 from 4.5 and I have no idea why I did that.