A really important chemical (D) is produced from available feedstock (A) in liquid phase reaction. At reaction conditions, A also degrades into undesirable impurity (U). The reactions are given as: A D rD = k1C 2 A A U rU = k2CA The reaction is carried out in two CSTRs with residence times of 2.5 min and 10 min respectively connected in series. The feed to the first reactor contains A and U with concentrations of CA0= 1.0, and CU0 = 0.3 (units are not important). At the end of first reactor, following composition is obtained: CA1 = 0.4 CD1 = 0.2 CU1 = 0.7 Find the composition leaving the second reactor.

A cylinder of 10-m-high, and a cross-sectional area of 0.1 m2 , has a piston (that is free to move) assumed to have negligible mass and thickness (see Figure 1(a)). Above the piston there is a liquid that is incompressible (constant density and volume) with ρliquid = 1000 kg/m3 . Below the piston there is air at 300 K, with a volume of 0.3 m3 . Assume air is an ideal gas (Ru =8.314 J.mol-1 .K-1 ; Mair = 28.9628 g/mol) Use P0 = 101.325 kPa and g = 9.807 m/s2 Find the following: a- The mass (in kg) of the liquid in the cylinder. b- The initial pressure of the air compartment. c- The initial mass of air (in kg). d- The initial internal energy of air. Another negligible mass and thickness piston is placed on top of the cylinder (see Figure 1b) and pushed down by 0.1 m to compress the air. The process is isothermal. The liquid is incompressible (its volume and phase do not change). Calculate: e- The final volume of air. f- The final temperature of air when thermal equilibrium is obtained. g- The final pressure of air. h- Does the internal energy of air change? i- The boundary work used to lower the piston located on top of the air. j- The total heat transfer outside of the piston from the air compartment.

A packed bed reactor with present of catalyst: A_(g) + 0.5 B_(g) --> C(g) . . -r_A’ = k C_A^0.33C_B^0.66 . A student is tasked with designing the reactor and predicting the output. The student forgets to take into account the effects of pressure drop on the design. For a packed bed reactor with 100 g of catalyst, the exiting concentration of C that the student determines is likely to be equal/ greater than the exiting concentration that is predicted to exist if pressure drop is taken into account. Explain? (Less than is wrong)

Identifying terms: (HINT: think “who, what, when, where and why?”)

Treaty of Tordesillas

The Great Schism

Please select one of casting methods which you think is the most suitable for the following object and give a description why you make this selection

1. Titanium hip joint                                    
2. Engine block of a motor car                                                  
3. a scale model toy car                                                       
4. Large steel sheet                                      
5. Pipes/tubing

Outline the chemical reactions which occur in the iron blast furnace as the burden descends from the top of the furnace, until it reaches the top of the slag pool in the hearth. Refer to both direct and indirect reduction.

Explain in terms of chemistry and heat balances why the furnace is considered to consist of three distinct zones (Preheating zone, Indirect reduction zone, Direct reduction and melting zone).

The magnitude of the liquid-phase diffusivity is much smaller than that of the gas-phase diffusivity -justify the steatment...

Why is the Paleozoic era sometimes called the era of Trilobites? How many different species of trilobites existed during the Paleozoic? Why is the Holocene epoch (modern times) called the age of “Insects”? How many species of insects are in existence today?

How can an increase in temperature lead to more ice? How long has this been happening/since when?

Please briefly explain the relationship between sedimentary rocks and fossil fuels.

The difference in temperature between the boiling refrigerant temperature and the evaporator outlet temperature is known as ___________.

1)How does the feed forward control loop anticipate disturbance ? Elaborate with an example.
2)It is well known that PLC is used for batch processes; however, SCSADA can be used for continuous processes as well;though, it is built on PLC. How is that possible ?
3) A good example of the application of proportional derivative ( PD ) controller is

please solve the questions at least two questions