An unknown gas has a pressure of 699.0 mm hg at 40.0 c. what is the temperature at standard pressure?

Hello!

An unknown gas has a pressure of 699.0 mm Hg at 40.0 C. What is the temperature at standard pressure ?

We have the following information:

P1 (initial pressure) = 699 mmHg

T1 (initial temperature) = 40 ºC (in Kelvin)

TK = TºC + 273.15 → TK = 40 + 273.15 → T1 (initial temperature) = 313.15 K

P2 (final pressure) = 1 atm (in STP) → P2 (final pressure) = 760 mmHg

T2 (final temperature) = ? (in Kelvin)

According to the Law of Charles and Gay-Lussac in the study of gases, we have an isochoric (or isovolumetric) transformation when its volume remains constant or equal, then we will have the following formula:

_______________________________

I Hope this helps, greetings ... Dexteright02! =)

n2(g) + 3h2-> 2nh3(g)   this is the balanced equation

note the mole ratio between n2, h2 and nh3.   it is 1 : 3 : 2   this will be important.

moles n2 present = 28.0 g n2 x 1 mole n2/28 g = 1 mole n2 present

moles h2 present = 25.0 g h2 x 1 mole h2/2 g = 12.5 moles h2 present

based on mole ratio, n2 is limiting in this situation because there is more than enough h2 but not enough n2.

moles nh3 that can be produced = 1 mole n2 x 2 moles nh3/mole n2 = 2 moles nh3 can be produced

grams of nh3 that can be produced = 2 moles nh3 x 17 g/mole = 34 grams of nh3 can be produced

note:   the key to this problem is recognizing that n2 is limiting, and therefore limits how much nh3 can be produced.