Agas containing water vapor has a dry-basis composition of 7.5 mole% co, 11.5% co2, 0.5% o2, and 80.5% n2. the gas leaves a catalyst regeneration unit at 620°c and 1 atm with a dew point of 57°c at a flow rate of 28.5 scmh [m3(stp)/h]. valuable solid catalyst particles entrained in the gas are to be recovered in an electrostatic precipitator, but the gas must first be cooled to 425°c to prevent damage to the precipitator electrodes. the cooling is accomplished by spraying water at 20°c into the gas. use simultaneous material and energy balances on the spray cooler to calculate the required water feed rate (kg/h). treat the spray cooler as adiabatic and neglect the heat transferred from the entrained solid particles as they cool. in terms that a high school senior could understand, explain the operation of the spray cooler in this problem. (what happens when the cold water contacts the hot gas? )