A countercurrent system is to treat (on an hourly basis) 10 tons of gangue (inert material), 1.2 tons of copper
sulfate, and 0.5 tons of water with water as a fresh solvent. The solution produced is 10 percemt copper
sulphate (remainder water). After each stage. 1 ton of inert retains two tons of water plus dissolved copper
sulphate. How many stages are needed for a 98 percent of copper sulphate recovery?

SEPA-LEACHING

Consider the titration of 50.0 mL of 0.0500 M Cu+ with 0.1000 M Fe3+ to give Cu2+ and Fe2+ using Pt and standard H+/H2 reference electrode to find the end point. The standard electrode potentials are E0Cu+/Cu2+=0.161 V and E0Fe2+/Fe3+=0.767 V. Calculate the actual electrode potential, E, at the following volumes of Cu2+ (i) 15, (ii) 25, and (iii) 26 mL

Choose one of the following spectroscopy fields and use the book/internet, to describe its principle (3-5 sentences) and applications (at least one example). (5 points each aspect, 10 points total) Rotational spectroscopy; Raman; Photoelectron; Fluorescence; Electronic; Vibrational; UV-Vis; or your own choice other than NMR

For a system coupled to a work reservoir and heat bath of temperature T, show that that the work done by the system (on the work reservoirs) is bounded from above by minus the change in Helmholtz free energy. ²

Flash distillation

A still is charged with 1000 moles of a 58.5 mole % methanol(M) and 41.5 mole % 1-propanol mixture. This mixture is distilled until 200 moles remain in the still and the cumulative distillate collected. You may assume that the relative volatility is 3.6 and it remains the same during the distillation process.

a) What are the feed and distillate flow rates during the process?

b) For the flas option, determine the equilibrium distillate and bottoms compositions

c) At what temperature does the flash tank operate?

d) What would you recommend, batch or flash? why?

Why would it be unreasonable to study the enthalpy of formation of Mg0(s) by directly using your Styrofoam calorimeter? Why is Hess's law a good way to study this reaction? Give one other example of a reaction that could not be studied using a Styrofoam container. (Hint: What solvents are used dissolve polystyrene?)

The consecutive liquid phase reactions k1 ,r1 k2 ,r2 k3 ,r3 . Estimate A −−→ B −−→ C −−→ D with first-order kinetics occur in a steady state CSTR. The feed composition for the CSTR is: CA0 > 0, CJ0 = 0, J = B, C, D. (a). Write mass balances for A, B, C, and D. From these, deduce that CJ’s, J = A, B, C, D, are related by a linear equation. Obtain expressions for CJ, J = A, B, C, D, in terms of CSTR space time τ. (b). Deduce qualitatively that CB and CC undergo maxima with respect to τ. Obtain condi- tions/expressions for optimum values of τ where CB and CC attain their individual maxima. (c). For k1 = 3 min−1, k2 = 2 min−1, and k3 = 1 min−1, estimate the optimum τ’s corre- sponding to maximum CB and CC and the corresponding reactor compositions, CJ’s, J = A, B, C, D.

1. The cycle involved in the operation of an internal combustion engine is called the Otto cycle. Air can be considered to be the working gas and assumed perfect. The cycle consists of the following steps.

1. reversible adiabatic compression from A to B
2. reversible constant volume pressure increase from B to C (from the fuel combustion)
3. reversible adiabatic expansion from C to D
4. reversible constant volume pressure decrease from D to A

Determine an expression for the efficiency of this engine assuming that heat is supplied in step ii). Then evaluate the efficiency for a compression ratio of 10:1. Assume that the ratio of the volumes defines the compression ratio and that state A is defined by V = 4.00 L, P = 1.00 atm, and T = 300 K. Further, let V_A = 10·V_B, P_C/P_B = 5, and C_p,m = (7/2)R. Finally, calculate the entropy change for system and surroundings for each step in the cycle.

please solve quickly. Waste heat from a chemical reactor is to run a boiler in a Rankine power cycle. The working fluid in the cycle is water. The boiler generates steam which exits at 300 psia and 1200°F. The condenser in the cycle runs at 3 psia, producing a saturated liquid. The turbine and the pump can be considered adiabatic and reversible. Assume the pump is driven by the turbinea.

a) Calculate the net work produced by the cycle, in Btu/lbm of steam. Wt=-524btu/lbm
b) What is the thermal efficiency of the process?
c) What percent of the heat entering the boiler is discharged from the condenser?

d) Carefully sketch a T-S diagram of this cycle, showing the temperatures of the streams between the processing units, and their locations relative to the phase boundaries. Label all axes.

Saturated steam at 300°C is used to heat a counter-current flowing stream of methanol vapor from 65°C to 240°C in an adiabatic (no heat exchange with surroundings) heat exchanger. The flow rate of methanol is 400 kg/minute, and the steam condenses and leaves the heat exchanger as liquid water at 90°C. Calculate the required rate of heat transfer from the water to the methanol in kW. Then, calculate the required flow rate of entering steam in m3/min.

Calculate H using plume rise equations for an 80 m high source (h) with a stack diameter = 5 m,
stack exit velocity = 12 m/s, wind speed at stack height = 1.9 m/sec,

Q=100g/sec. stack gas temperature = 80 oC (353 K), ambient temp = 25 o C (298 K), and sunny day with stability condition

Determine the total plume height (_________) m
Determine the sigma z at the distance for MGLC. (____________) m
Calculate the distance for MGLC (__________) Determine MGLC at its location on the centerline. (____________) micro-gram/m3

will upvote, thanks!

6. Distillation: Why do we need reflux to return back to distillation columns? How the reflux ratio will affect the design and operations of distillation process.

As an engineer in your firm, you are tasked with decreasing the pressure drop across a packed column. Would you increase or decrease the packing size with all the operating variables held constant? Justify.

Using the Fenske equation, an engineer determines that the number of stages for a given separation is 12. For the same conditions, the engineer wants to operate the distillation column using 15 equilibrium stages to achieve the desired separation. Is it possible? Justify your answer