Arigid copper tank, initially containing 1 m3 of air at 295k, 5 bar, is connected by a valve to a large supply line carrying air at 295k, 15 bar. the valve is opened only as long as required to fill the tank with air to a pressure of 15 bar, at which point the air in the tank is at 310k. the copper tank, which has a mass of 20 kg, is at the same temperature as the air in the tank, both initially and finally. the specific heat of the copper is c = 0.385 kj/kg-k. assuming ideal gas behavior for the air, determine (a) the initial and final mass of air within the tank, each in kg, and (b) the heat transfer to the surroundings from the tank and its contents, in kj, ignoring kinetic and potential energy effects. (630)

technology is the collection of techniques, skills, methods, and processes used in the the merriam-webster learner's dictionary offers a definition of the term: "the use of moreover, these technologies have become so complex that entire fields more recently, modern works of science fiction such as those by philip k.

explanation:

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂

blue light is scattered in different directions by the tiny molecules of air. blue is scattered more than other colours because it has a shorter distance to travel which results in smaller waves. this is why we see a blue sky most of the time.