What is the temperature of 0.80 mol of a gas stored in a 275 ml cylinder at 175 kpa?

              7.23 K

Data Given:

                 Moles  =  n  =  0.80 mol

                 Temperature  =  T  =  ??

                  Pressure  =  P  =  175 kPa  =  1.727 atm

                  Volume  =  V  =  275 mL  =  0.275 L

Formula Used:

Let's assume that the gas is acting as an Ideal gas, then according to Ideal Gas Equation,

                  P V  =  n R T

where;  R  =  Universal Gas Constant  =  0.082057 atm.L.mol⁻¹.K⁻¹

Solving Equation for T,

                  T  =  P V / n R

Putting Values,

      T  =  (1.727 atm × 0.275 L) ÷ (0.80 mol × 0.082057 atm.L.mol⁻¹.K⁻¹)

      T  = 7.23 K

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"