Explanation:
Combustion of butane gives following reaction
C4H10 + 13/2 O2 → 5H20 + 4CO2
Therefore, One Kg of Butane consists of 1000/58 moles . That is 17.24 moles.
17.24 moles of butane reacts with (6.5×17.24) moles of O2 = 112.06 moles = 3.586 Kg O2.
Weight % of O2 in Air = 20 %
Mass of theoretical air used is 3.586×5 = 17.93 Kg = 71.72 %
The dew point temperature of H2O is :
D = (237.3×B)/(1-B)
B = ln(E/6.108)/17.27
E is vapor pressure at given temp.
At T = 30° C , E = 31.8 mm of Hg = 41.84 Milli Bars
B = 0.1114
D = 29.74°C