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

You use the atomic number to find out how many protons and neutrons there are in the atom. you use the atomic mass to find out how many protons and electrons there are in the atom. 

Is a logical series of steps

The answer to your question really depends on three things: how much water you have, how cold it is to start out, and how cold the things around it are. water actually freezes when it gets to 32 degrees fahrenheit (0 degrees celsius), but the time it takes to get there may be different.  let's start with the first. if you take two glasses, and fill one with a tiny bit of water, and the other about halfway, then put them both in the freezer, the one with less water will freeze first (you can try this at home, but i recommend using plastic cups and not glass ones).  now let's move on to the second part. let's say you have two glasses, and you fill one with really cold water that has been in the refrigerator, and the other with really hot water from the sink. if you put both of them in the freezer, the one that started out colder will freeze first.  for the third part, let's imagine that you have two glasses with the same amount of water in them, and the water is at the same temperature. imagine putting one outside on a really really cold day in georgia, and having a friend in alaska put one outside on the same day. since it would be so much colder in alaska, the glass of water there would freeze before yours.  so, if you took a tiny bit of really cold water in a glass, and put it outside on a cold day in alaska, it would freeze a lot faster than a big glass of hot water outside on a cold day in georgia. 

Answerδh > 0explanationc₆h₆  (s)  → c₆h₆ (l)if you are changing it from a solid to a liquid, you are pretty much melting the solid. this requires heat energy. therefore, the reaction is endothermic (takes in energy); the system enthalpy increases as the reaction proceeds: δh > 0.