The specific internal energy of formaldehyde (HCHO) vapor at 1 atm and moderate temperatures is given by the formula: = . + . ^ where T is in C.

(a) Calculate the specific internal energies of formaldehyde vapor at 0C and 200C. What reference temperature was used to generate the given expression for U^?

(b) The value of U^ calculated for 200C is not the true value of the specific internal energy of formaldehyde vapor at this condition. Why not? Briefly state the physical significance of the calculated quantity.

(c) Use the closed system energy balance to calculate the heat (J) required to raise the temperature of 3.0 mol HCHO at constant volume from 0C to 200C. List all of your assumptions.

(d) From the definition of heat capacity at constant volume, derive a formula for ()[/ ]. Then calculate the heat (J) required to raise the temperature of 3.0 mol of HCHO(v) at constant volume from 0C to 200C