The standard reaction enthalpy for the decomposition of CaCl2 · NH3(s) into CaCl2(s) and NH3(g) is nearly constant at +78 kJ mol−1 between 350.K and 470.K. The equilibrium pressure of NH3 in the presence of CaCl2 · NH3 is 1.71 kP a at 400.K. Find an expression for the temperature dependence of ∆rG◦ m in the same range.

Amass of 1.5 kg of air at 120 kpa and 24°c is contained in a gas-tight, frictionless piston-cylinder device. the air is now compressed to a final pressure of 720 kpa. during the process, heat is transferred from the air such that the temperature inside the cylinder remains constant. calculate the boundary work input during this process.

The thermal expansion or contraction of a given metal is a function of the f a)-density b)-initial temperature c)- temperature difference d)- linear coefficient of thermal expansion e)- final temperature f)- original length

The higher the astm grain size number, the finer the gran is. a)-true b)-false