Ammonium sulfate ((nh4)2so) is dried from 4.0% to 0.2% moisture in a countercurrent rotary drier. hot air at 363 k and containing 0.01 kg/kg dry air is admitted at one end of the drier feed, flows countercurrently in contact with the solids, and leaves at the other end of the drier at 305 k. the solid enters at 298 k and leaves at 333 k. the heat loss from the drier is estimated to be 4 x 104 kj/hr. estimate the air requirement for the drier (in kg/hr) for producing ammonium sulfate at the rate of 1000 kg/hr. data: latent heat of vaporization of water at 273 k = 2502.3 kj/kg! heat capacity of dry air = 1.005 kj/kg. k heat capacity of water vapor = 1.884 kj/kg. k heat capacity of water = 4.2 kj/kg. k heat capacity of dry (nh4)2so4 = 1.507 kj/kg. k

1.) which of the following is a molecule but not a compound? a.he b.f2 c.h2o d.ch4 2.) what is a physical combination of substances? a.a compound b.a molecule c.a mixture d.an element 3.) what is a chemical combination of substances? a.a compound b.an atom c.a mixture d.an element 4.) what is the relationship between the solute and solvent in a solution? a.they form a compound b.they form a mixture c.they form molecules d.they form chemical bonds 5.) the gases in air dissolve in water. what would be one way to reduce the amount of a gas dissolved in water? a.add more water b.reduce the air pressure c.increase the air pressure d.stir the water 6.) how would you determine the solubility of a substance? a.find how well it dissolved various substances. b.find the mass and the volume of the substance. c.find the temperature at which the substance evaporated. d.find how much i was able to dissolve in a solute. 7.) the periodic table organizes all of the kinds of a.molecules. b.compounds. c.atoms. d.ions. 8.)what distinguishes two substances combined to become a compound vs. two substances combined to become a mixture? a.whether they can be easily separated b.whether they chemically bond together c.whether they both are visible d.whether they are heterogeneous 9.) the principle components of air are: n2 78% o2 21% ar 0.95% co2 0.038% this is a solution of a.molecules and atoms. b.molecules. c.compounds and molecules. d.atoms.