Carbon dioxide (CO₂) at 1 bar, 300 K enters a compressor operating at steady state and is compressed adiabatically to an exit state of 10 bar, 540 K. The CO₂ is modeled as an ideal gas, and kinetic and potential energy effects are negligible.


For the compressor, determine:

(a) the work input, in kJ per kg of CO₂ flowing,

(b) the rate of entropy production, in kJ/K per kg of CO₂ flowing, and

(c) the percent isentropic compressor efficiency.

1. A 3 L container is filled with 12 moles of N₂ at -140.6 °C. Calculate the pressure using ideal gas equation, van der Waals equation, SRK equation, virial equation, and the compressibility factor chart correlation.

1. Using Antoine’s equation, derive an expression to calculate heats of vaporization as a function of the A, B and C constants in Antoine’s equation and temperature. Use the derived expression to calculate heats of vaporization of water and benzene at their boiling points and 1 atm pressure. Compare the results with tabulated values of water and benzene.

130 kg of uniform spherical particles with a diameter of 60 mm and particle density 1500 kg/m³ are fludised by water (density 1000 kg/m³, viscosity 0.001 Pa s) in a circular bed of cross-sectional area 0.2 m². The single particle terminal velocity of the particles is 0.98 mm/s and the voidage at incipient fludisation is known to be 0.47. Determine:

a. The minimum fludised velocity            

b. height when the liquid flow rate is 2x10^-5 m³/s.  

Describe the differences between the following and listany particular advantages possessed by one over the other:

(a) phototubes and photomultiplier tubes .

A pickle factory discharges brine with a salt concentration of 7 g/L at a flow of 4.5 m3/s to a river with a flow of 150 m3/s and a salt concentration of 150 mg/L upstream of the pickle factory. The salt concentration in the river cannot exceed 400 mg/L.

(a) Is the factory in compliance with this standard? Support your answer with calculations. (pay attention to units!)

(b) Describe (in complete sentences) at least one potential environmental impact of the brine. It is not sufficient to copy and paste words from the lecture slide, you need to explain the issue.

An isothermic reaction is carried out adiabatically and the CSTR reactor design algorithm is shown as below:

The reaction is second order in A. The feed which is equimolar in a solvent and A, and its enters the reactor at a total volumetric flow rate, v0 of 10 dm3/min with the initial concentration of A being 4 M. The rate constant, k given as 0.1 dm3/mol.min at 380 K. Determine the conversion can be achieved in 600 dm3 CSTR by using the following methods:

a) Graphically

b) False position method with initial guesses of Xl =0.6 and Xu =0.9

c) Secant method with initial estimates of X-1 = 0.6 and X0, =0.9

Iterate until the approximate error falls below 1 %. Find the absolute relative approximate error at the end of each iteration.

Which answer is a reasonable paraphrase of the Precautionary Principle applied to atrazine by many European nations?

4. Suppose that you are the engineer in the charge of the gasification section of the Acme Substitute Natural Gas Company. ASNG Co. runs fixed-bed, dry-ash gasifiers. The raw gas is cleaned, shifted, and sent to a methane synthesis unit. Every morning you receive a report from ASNG’s analytical laboratory on the characteristics of the coal that will be fed to the gasifiers during the next day’s operations. One important characteristic is the ash fusion temperature (AFT), i.e., the temperature at which the ash will begin to melt and form a liquid slag. It is vitally important to keep the bed temperature not only below the AFT, but usually ≥100°C below, to allow for a margin of safety. One day the lab report indicates that the AFT for the coal about to go to the gasifiers is substantially lower than it has been in recent weeks. (a) What instructions will you issue to the plant operators for adjusting the steam/oxygen ratio being fed to the gasifiers? (b) Why? (c) What impact will this change have on the H₂/CO ratio in the product gas? (d) Why? (e) How will this change affect operation of the water-gas shift unit? (f) Why?

With your own words, explain what a colligative property is. Give one detailed example.

Rank methyl, primary, secondary and tertiary radicals, carbons and -carb cations, after increasing stability. Give examples.

Explain how the temperature is controlled on the (a) top (b) middle (c) bottom part of the tower in separation systems.

Compare and contrast the three types of plates in plate distillation systems.