Please consider a poorly insulated compressor that was in need of maintenance. The compressor consumed 1.00 kW and took in R-22 at -15°C and 1 bar. The R-22 exited at 10 bar. Irreversibilities within the compressor generated entropy at the rate of 0.100 kJ/kg- K. The compressor leaked heat at the rate of 8.19 kJ/kg at an effective temperature of 300°K.

a. Please take the Compressor as the system and make a sketch. Also, please use this space to keep a list of the assumptions you make while addressing Parts b-g of this problem.

b. What type of system is the compressor? Please use a sentence or two to explain.

c. Please write and reduce the Mass Rate Balance (E4.4.2) for the system.

d. Please write and reduce the Energy Rate Balance (Eq. 4.15) for the system.

e. Please write and reduce the Entropy Rate Balance (Eq. 6.34) for the system.

f. Please determine Te in C.

g. Please determine m in kg/sec.

1. In refrigeration, heat removal occurs
   1. during evaporation.                 c. during compression.
   2. during condensation.              d. during throttling.
2. Flow of refrigerant through the throttling valve of a refrigeration system occurs at constant
   1. entropy.                                  c. temperature.
   2. Internal energy.                      d. enthalpy.
3. Refrigerant flows through the coil on the back of most refrigerators. This coil is the
   1. condenser.                              c. evaporator.
   2. compressor.                            d. heat exchanger.
4. Which of the following refrigeration cycle deviation from ideal is considered desirable?
   1. Pressure drops through the connecting tubes.
   2. Subcooling of the refrigerant in the condenser.
   3. Superheating of the vapor entering compressor.
   4. Friction of the compressor blades.

Explain which methods can be used for tuning PID controllers.
Principles / advantages / disadvantages etc.

What determines the respective isotherm line for corals? Eastern phoebe (bird)? Bats?

Explain what a P‐, PI - and a PID controller are, and present important characteristics for these controllers

Give examples of a variety of relevant types of dynamic systems, e.g. 1st order, 2nd order,
time delay, integration, reinforcement etc. Explain how these occur in practice and explain
for important properties of these systems.

James has ten heavily crosslinked epoxy ‘cubic blocks’ with dimensions of 1.0 cm by 1.0 cm by 1.0 cm and a density of 1.05 g/cm3 . Tom has twenty blocks made of the same material by double in length scale of those owned by James. Piter has only one block made of the same material, but his block is five times the length scale of those owned by James. (a) What is the number-average mass of all of the blocks? (b) What is the surface-area-average mass of all of the blocks? (c) What is the volume-average mass of all of the blocks?

Air enters a counter-flow drier at 70˚C dry bulb temperature and 20˚C dew point temperature. Air leaves the drier at 40˚C and 60% relative humidity. The initial moisture content of the product is 82% (wet basis). The amount of air moving through the drier is 2000kg of dry air per hour. The mass flow rate of the product is 10kg dry solid per hour. What is the final moisture content of the dried product in wet basis?

Estimate the value of the apparent contact angles (q*) for a composite interface formed by Water on an electrospun surface of PMMA + 44.1 wt% POSS.
The average fiber radius (R) = 500 nm and the average inter-fiber spacing (D) = 4.5 µm. The Young’s contact angle (q) for water on a spin-coated PMMA + 44.1 wt% POSS surface = 123°.
Also, compute the values of the two design parameters D* and A*. Note the capillary length (L cap) for water = 2.8 mm. Based on the value of A*, estimate the breakthrough pressure for water on this electrospun surface. Also, estimate the height of a column of water that would provide this breakthrough pressure.

11. Please indicate the type of oxide (acid, basic or amphoteric) that best describes each of the following compounds. Explain the reasoning for your selection.

a) MgO
b) SnO
c) CO₂
d) Al₂O₃

Note that this is an Inorganic Chemistry subject. Please answer in an organized matter. Use a legible handwriting so that the answers can be understood. Thanks in advance!

Given the following data, what is the value of ΔGf° (CH3OH(ℓ) at 25°C?

CO(g) + 2 H2(g) ⇄ CH3OH(ℓ)   K = 1.081 × 10-40

ΔGf°(CO) = -137.2 kJ/mol

9. Draw a picture of the following solid structures:
a) bcc
b) fcc
c) simple cubic
In each, determine the coordination number of a sphere in each of them.

Note that this is an Inorganic Chemistry subject. Please answer in an organized matter. Use a legible handwriting so that the answers can be understood. Thanks in advance!

6. The following species: O₂ (dioxygen), O₂^- (peroxide ion) and O₂^2- (superoxide ion) are known. Using the TOM, construct the OM energy diagram for each species. Based on them, organize them in increasing order of:

a) bond order
b) bond length
c) Bond dissociation energy

Note that this is an Inorganic Chemistry subject. Please answer in an organized matter. Use a legible handwriting so that the answers can be understood. Thanks in advance!