Energy is released when hydrogen and oxygen react to produce water. This energy comes from the fact that the final hydrogen-oxygen bonds represent a lower total energy states compared to the original hydrogen-hydrogen and oxygen-oxygen bonds. Calculate how much energy (in kilojoules per mole of product) is released by the reaction:

1/2 O2 + H2 → H2O

at constant pressure and given the following standard bond enthalp enthalpies denote the enthalpy absorbed when bonds are broken at ture and pressure (298 K and 1 atm).

H-H : 432 kJ/mol
O=O : 494 kJ/mol
H-O : 460 kJ/mol

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Determine whether or not it is possible to compress air adiabatically from k to 140 kpa and 400 k. what is the entropy change during this process?

Atmospheric air has a temperature (dry bulb) of 80° f and a wet bulb temperature of 60° f when the barometric pressure is 14.696 psia. determine the specific humidity, grains/lb dry air. a. 11.4 c. 55.8 d. 22.5 b. 44.1