Question

P4B.3 Prior to the discovery that freon-12 (CF,Cl,) is harmful to the Earth's 0zone layer it was frequently used as the dispersing agent in spray cans for hair spray etc. Estimate the pressure that a can of hair spray using freon-12 has to withstand at 40 °C, the temperature of a can that has been standing in sunlight. The enthalpy of vaporization of freon-12 at its normal boiling point of-29.2°C is 20.25 kJ mol; assume that this value remains constant over the temperature range of interest.

Answer 1

Atrap = Kylmol. Tepsperatures T1 = -2982°c = 243.95k T2 = 42°c = 315.15k P1 = 1 atm. R = 8.314 8163 . We know, definite integral & P₂= ? clausius-clapeyson equation- en la) - slike winnas 243.95 3 15.15 ( 1 20. 25 3 15.15 lu() 2005 i (2015 - Show 243.95 8:3) 4X10 TP2 = 9:54 atm Hence pressure = 9.54 atm.