A furnace wall is composed of three layers: 15 cm of firebrick [k = 1.5 W/(m*K)], followed by 22.5 cm of kaolin insulation brick [ k = 0.075 W/(m*K)], and finally followed by 4 cm of masonry brick [ k = 1.0 W/(m*K)]. The temperature of the inner wall surface (firebrick) is 1400 K and the outer surface (masonry brick) is at 350 K. Assume each layer has an area normal to the direction of heat flow equal to 1 m^2.

a.) What is the temperature at the firebrick-kaolin interface?

b.) What is the temperature at the kaolin-masonry interface?

c.) Across what material is the temperature drop the highest?

write a 4 pages report discussing the evaluation into south african coal export trends through the past25 years. Are the demands being met? guys as soon as possible.....

***Fluid Flow***

What is the difference between using venturi meters vs orifice meters? Is there an advantage for using one over the other the two?

7.7) If 23.70 mL of 0.0400 M KMnO4 is required to titrate a 0.400 g sample of K3[Fe(C2O4)3]⋅3H2O, what is the percent C2O2−4 in the complex?

A sample containing precious chemicals (MF and BAD) is given to you to analyze anddetermine the molar compositions. You can’t measure MF directly so you must send itthrough a reactor where it reacts with BAD in three reactions:

R1: MF + BAD→MAD + FB
R2: MF + 3BAD→B2 + F(AD)3 + MB R3: 2MF + 3BAD→2MBAD + 2FD+BA

The selectivity of FB to MB is 13.4 and the selectivity of B2 to BA is 165. If your equipment detects 2 moles of BA:

What is the molar composition of the original sample?

Can you determine the product stream composition? If so, what is it?

1. Compare and contrast primary and secondary treatment in septic tanks. What are the goals/desired outcomes? How are those achieved in each system?

Similarity:

Primary:

     Goal or outcome =

    How achieved =

Secondary:

            Goal or outcome =

            How achieved =

An ideal gas known as Minesium (MW=34.0) is flowing at a steady rate of 0.125 lbmol/min through a 62.5 in2 circular tube at a temperature of 185 °F and pressure of 42.0 psig. What is the velocity (ft/s) of this ideal gas? Assume Patm = 14.7 psia. The correct answer is 0.586 ft/s, but I don't understand how to get this answer.

Two representative pollutants are radon (²²²Rn) and benzene. Parameters needed for the estimation are listed in the table below. Answer the following questions.

(a) Estimate the steady-state radioactivity in the station in Bq m^-3.

(b) Estimate the steady-state concentration of benzene both in mg m^-3 and in ppbv. Molecular weight of benzene is 78 g mol^-1. Assume 298 K and 1 atm (= 101,325 Pa).

(c) Although regulatory limit of indoor benzene concentration is 30 mg m^-3 in Korea, researchers argue that it should be as low as 1.3 mg m^-3 considering carcinogenic risk of benzene. Can you lower the benzene concentration as low as for protection of citizens’ health? Suggest potential options to lower benzene concentration in the station.

All statements are thermodynamically correct, EXCEPT:

a) The Gibbs free energy variation for vaporization under T and P constants is always positive
b) If a saturated liquid undergoes reversible adiabatic expansion to a lower pressure, then some of the liquid will vaporize
c) The heat capacity at constant pressure of a monocomponent system consisting of liquid and vapor in equilibrium is infinite
d) The heat capacity at constant volume of a monocomponent system consisting of liquid and vapor in equilibrium is infinite

we discussed two-film theory and the use of the overall mass transfer coefficients that will be one of our foundational components in solving practical mass transfer problems over the course of the semester. In your own words, explain what two-film theory is and how it simplifies real mass transfer across an interface? How does the overall mass transfer coefficient develop from two-film theory? Finally, what is the difference between the overall mass transfer coefficients based on the gas and liquid phase and why might we use one over the other?