# science-gas laws

posted by .

I got 2 questions for ya:

1. Calculate the new pressure of an oxygen tank at 127o C if the tank had 2200 psig at room temperature (22o C)?

I used Gay Lussac's law.
Here's my work:

P1= 2200psi
P2= X
T1= 295K
T2= 400K

(2200x295)400= X
I got 2983psi

Is that correct?

2. Given 320 mL of saturated gas at 760 mm Hg and 25o C), what would be the volume under dry conditions at the same pressure and temperature? [water vapor pressure at 25o = 23.78 mmHg]

I got sorta confused on this one but here's what I came up with.

I used the combined gas law.

P1= 760mmHg - 23.78mmHg = 736.22
**Is this correct? I was a little iffy on this figure.**
V1= 320mL
T1= 298K
P2= 760mmHg
V2=X
T2= 298K

My work: ((736.22)(320)(298))/(298x760) = 309.98 or 310mL

Hopefully I'm good on this one too.

Thanks a bunch. If anything is wrong please point it out to me.

• science-gas laws -

P1= 2200psi
P2= X
T1= 295K
T2= 400K

(2200x295)400= X
I got 2983psi
and I get 2983, also, but I don't know how you got that answer with the math.
P1/T1 = P2/T2 and
P2 = (2200 x 400)/295. If I do your math it gives 1622. Hopefully, you just typed it in wrong. You know if T goes up the P must go up. Check my thinking.

The second problem looks ok to me.