1.Explain the methods are used to avoid material hazards.

2. Explain the control measures for overpressure

3. Explain the Process Design Strategies

4.Describe the Flash point and Auto Ignition temperature

5.Explain the causes of Dust explosions in detail.

A diffusion process is run at 1200 ºC with the surface concentration of diffusing atoms kept constant at 1024 atoms/m3 . The process is run for 3 h. If there are no diffusing atoms at the start of the diffusion process inside the diffusing material, at what depth below the surface is the concentration of atoms 1022 atoms/m3 ? The diffusion coefficient at 1200ºC is 7.0 X 10-17 m2 /s.

Calculate the pressure drop across a stenosis of diameter 6mm in the femoral artery in which the crosssection is reduced to one-third of normal if the flow rate through the artery is 50cc/min, and the upstream pressure is 100 mmHg?

A)

Explain what is Fugacity (provide an explanation as detailed as possible). Explain how the fugacity criteria for VLE and Chemical reactions is related to the concept of increasing entropy

B)

What are internal Energy and Enthalpy? how are they related?

C)

A mixture of water-ethanol containing a significant amount of methanol is being distilled (separation by VLE). Someone tells you that the methanol is not a problem because it boils off first as it has a lower boiling point. Is this true? Discuss in detail.

A 2-in-ID wetted wall column is being used to strip CO2 from an aqueous solution by an air stream at 1.0 m/s. At one point in the column, the concentration of CO2 in the air stream is 1.5 mole percent. At the same point in the column, the concentration of CO2 in the water is 0.5 mole percent. Determine the gas-mass-transfer coefficient kG (kg mole/atm-m2-s) and the mass flux at the point in the column. The column is operated at 10 atm and 25°C. The Henry’s constant of CO2 in water at 25°C is 1.64 × 103 atm/mole fraction CO2 in solution.

Write down the equation for the rate of entropy production, diS/dt, for the Bernoulli process 0⇄1 with states 0 and 1, forward rate constant w10 and reverse rate constant w01. Reformulate the equation to eliminate the summation of logarithmic terms. Use your final result to calculate the equilibrium distribution. What are the equilibrium probabilities of states 0 and 1 if w10=w01. Calculate the equilibrium entropy, S°, of the system for w10=w01. 6

The first step in the production of high purity silicon for semiconductors is represented by this equation. SiO2(s) + 2C(s) → Si(s) + 2CO(g) H° = +689.9 kJ

a. Calculate Hf° for SiO2(s). Given: Hf° for CO(g) = –110.5 kJ·mol–1

b. Find Srxn for the production of pure silicon. Given: S° for C(s) = 5.7 J·K–1 ·mol–1 , for CO(g) is 197.6 J·K–1 ·mol–1 , for Si(s) = 18.8 J·K–1 ·mol–1 , and for SiO2(s) = 41.8 J·K–1 ·mol–1

c. Determine G° for the reaction at 25 °C.

d. Find the minimum temperature in °C at which this reaction is spontaneous. Assume that H° and S° do not vary with temperature.

Estimate:

b) LFL and the UFL at 25 ºC of 1 vol % hexane, 1 vol % ethylene, 3 vol % methane, 95% vol air. c) LFL and the UFL for hexane individually at a temperature of 300 ºC. Use the lower heat of combustion of 921.4 kcal/mol. ( Use flammable mole fraction)

A waste gas stream

containing 5.5% ammonia in air is being stripped of the bulk of the ammonia by absorbing it in water in a tray tower. The liquid to gas ratio on a molal basis is known to be 2.5. Both the inlet gas and inlet water streams enter at 25oC. The inlet and outlet gas streams may be assumed to be saturated with water vapour. During operation a thermocouple in the outlet liquid stream measures a temperature of 35.2oC.

a)Calculate the mole fraction of ammonia on the outlet gas stream and hence the percentage recovery of ammonia in the column

b)Determine the number of ideal stages required for this separation

Data:Heat of Solution= 37000kJkmolNH3-1

Specific Heat of Water= 75kJkmol-1oC-1

Equilibria: In the equation y=mx,

25oC m=0.97

30oCm=1.22

35oCm=1.53

A gas mixture containing 80.0 mole% N₂ and the balance n-hexane flows through a pipe at a rate of 100.0 m³/h. The pressure is 2.00 atm absolute and the temperature is 140.0°C.

a. What is the molar flow rate of the gas?  

b. To what temperature would the gas have to be cooled at constant pressure in order to begin condensing hexane?

c. To what temperature would the gas have to be cooled at constant pressure in order to condense 85.0% of the hexane?

A gas mixture contains 20.0 mole% H₂O(v) and 80.0 mole% N₂.

The gas temperature and absolute pressure at the start of each of the three parts of this problem are 66°C and 700.0 mm Hg.

Ideal gas behavior may be assumed in every part of this problem.

a. If some of the gas mixture is put in a cylinder and slowly cooled at constant pressure, at what temperature would the first drop of liquid form? °C

b. If a 30.0 liter flask is filled with some of the gas mixture and sealed, and 30.0% of the water vapor in the flask is condensed, what volume would be occupied by the liquid water?  cm³

What would be the system temperature? °C

c. If the gas mixture is stored in a rigid-walled cylinder and a low-pressure weather front moves in and the barometric (atmosopheric) pressure drops from 760 mm Hg to 720.0 mm of Hg, what would be the new gauge pressure in the cylinder?  mm Hg

Please work out and explain. Thanks.

A stream of gas mixture of Acetone and Nitrogen is at Pgauge = 8 atm. If the partial pressure of acetone is pA= 500 mmHg, and the barometer reads Patm = 760mmHg, what is

a) the total pressure of this gas stream [mmHg-abs] and partial pressure of nitrogen

b) the mole fraction of acetone in the gas stream

c) If the volume flow rate of this gas stream is 1m^3/min, what is the component volume flow rate of acetone?

Describe the microstructure resulting from precipitation hardening and what the structure looks like on a phase diagram

1) How i measure the chromatography step by step?

2) How i measure the Spectrscopy step by step?

The synthesis reaction is highly exothermic; therefore, cooling water must be pumped through the jacket of the reactor to maintain a stable temperature. Find the enthalpies of the main reaction and side reaction. (Use Hess’ law if necessary.) Based on the heats of reaction, calculate the necessary rate of cooling, and the rate of cooling water flow required. (Cooling water is available at 5oC, with max ΔT = 15oC)

Main: C3H6 + 1.5O2 --> CO2 + H2O

side: C3H6 + 4.5O2 --> 3CO2 + 3H2O

Based on the data from the previous question, select an appropriate pipe size from the NPS schedule for your cooling water flow. Fluid velocity should be at least 1.5m/s to prevent the fouling of the pipes.