How many moles of gas would occupy a 25.0 liter when the temp is 22.0 degrees celsius and the pressure is 646 torr

0.877 mol  

Step-by-step explanation:

We can use the Ideal Gas Law to solve this problem.

pV = nRT     Divide both sides by RT

 n = (pV)/(RT)

Data:

p = 646 torr

V = 25.0 L

R = 0.082 06 L·atm·K⁻¹mol⁻¹

T = 22.0 °C

Calculations:

(a) Convert the pressure to atmospheres

p = 646 torr × (1 atm/760 torr) = 0.8500 atm

(b) Convert the temperature to kelvins

T = (22.0 + 273.15) K = 295.15 K

(c) Calculate the number of moles

n = (0.8500 × 25.0)/(0.082 06 × 295.15)

  = 0.877 mol