Steam at a temperature of 280 DegreeC flows in a steel pipe (k=70 W/m K) having an inner and outer diameter of 5 cm and 5.6 cm. The pipe is covered with glass wool insulation (k=0.05 W/m K) to a thickness of 4 cm. On a windy day heat is lost from the lagging surface with a convective heat transfer coefficient of 50 W/m2 K. The surroundings are at a temperature of 5 DegreeC and the internal heat transfer coefficient for heat transfer between the steam and the steam pipe is 600 W/m2 K.
What are the rate of heat loss from pipe per unit length and the outer surface temperature of the lagging?
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Ethanol can be produced commercially by the hydration of ethylene:
C2H4 + H2O -> C2H5OH
Some of the product is converted to diethyl ether in the side reaction:
2C2H5OH -> (C2H5)2O + H2O
The feed to the reactor contains ethylene, steam, and an inert gas. A sample of the reactor effluent gas is analyzed and found to contain 43.3 mol% ethylene, 2.5 mol% ethanol, 0.14 mol% ether, 9.3 mol% inerts, and the balance water.
a. Take as a basis 100 mol of effluent gas, draw and label a flowchart, and do a degree of freedom analysis based on an atomic species balance.
b. Calculate the molar composition of the reactor feed, the percentage conversion of ethylene, the fractional yield of ethanol, and the selectivity of ethanol relative to ether.
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Question 3 Steam enters an adiabatic turbine at 800 psia and 900oF and leaves at a pressure of 40 psia. Determine the maximum amount of work that can be delivered by this turbine.
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1.) what are electron levels? Please describe.
2.) explain how the number of protons, electrons, neutrons and electron energy levels are related on the periodic table.
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Determine the thermodynamic state of 1,1,1,2-Tetrafluoroethane (R-134a) at 102 °C and 1000 kPa. Critical Pressure= 4.059 MPa, Critical Temperature = 101.06°C.
*I keep getting stuck with a quadratic equation and two volume values, when using the van der Waals equation of state (P=(RT/(V-b))-(a/V^2))....I am determining the thermodynamic state by finding if the compressibility factor (z) is less than or greater than 1, to find if attractive or repulsive forces dominate.
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Let’s explore the scientific method. Here is the situation: We are planting a garden. We have a variety of bulbs and potted plants. We do not have any directions on how or when to plant each of these items. We do not have any gardening books, magazines, or access to the Internet (Oh, the horror!). We need to observe a number of characteristics for these plants. What are some of the characteristics that we want to observe? What might be your initial hypothesis? How would you set up an experiment to test your hypothesis?
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What are the heat capacity constant (Cp) values for C10H8 ,O2 , C8H4O3 ,CO2 and H2O at 600 K according to the Antoine equation?
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A set of four group orbitals derived from four 3s atomic orbitals in necessary to examine the bonding in [PtCl4]-, a square planar complex. Deduce the wave function equations for these four SALCs using the 3s labeling scheme specified, starting with the irreducible representations for these group orbitals. Using sketches of the deduced orbitals, symmetry characteristics of the representation, and a coefficient table like in Section 5.4.4, deduce the SALCs not derived initially from the character table analysis. Provide normalized equation and sketch each group orbital.
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Electrolyte balance is necessary to maintain homeostasis. What are those electrolytes? Which are cations and which are anions? What are the normal values for humans? How can they be replaced? Which IV fluids contain which electrolytes?
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You are provided with some weight of specimen data as a function of time following exposure of
an alloy specimen to oxygen at high temperature.
(i) Determine whether or not the alloy follows a particular oxidation rate law during the
initial one hour period; if so, specify which one and determine the oxidation rate constant.
(ii) Is there any change in the oxidation rate law in the following 20 hour period? If so,
specify the new law and estimate the oxidation rate constant.
(iii) Account for the change in oxidation rate after 25 hours exposure and calculate the
relevant oxidation rate constant in the period : 25 hours to 100 hours.
Total surface area of specimen : 10cm²
Initial weight of specimen : 1000 mg
Oxidation time Weight of specimen Oxidation time Weight of specimen
(mg) (mg)
1 minute 1000.1 15 h 1023.2
2 minute 1000.2 20 h 1026.3
5 minute 1000.5 25 h 1029.0
20 minute 1001.9 30 h 1029.5
40 minute 1004.1 40 h 1030.0
60 minute 1005.9 50 h 1025.0
2 h 1008.3 70 h 1015.0
3 h 1010.2 80 h 1010.0
4 h 1011.5 100 h 1000.0
10 h 1018.7
(iv) If the corresponding scale thickness data are as follows, plot the relationship between y and t for the full period: 0 to 100 hours.
Oxidation time Scale thickness (µm)
0 minutes 0
5 minutes 0.5
40 minutes 3.9
60 minutes 5.8
10 hours 18.9
20 hours 26.0
25 hours 28.0
30 hours 28.5
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Methane is compressed adiabatically in a pipeline pumping station from 3500 kPa and 35°C to 5500 kPa at a rate of 1.5 kg mol·s−1. If the compressor efficiency is 0.78, what is the power requirement of the compressor and what is the discharge temperature of the methane? ( if you could explaine it step by step )
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what is vital records, what do they do, and what kind of information do they get?
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1) A business model is a plan that details how a company creates revenue.
a) True
b) False
2) The benefits of Business 2.0 include content sharing through open sourcing, user-contributed content, and collaboration inside and outside the organization.
a) True
b) False
3) The main advantage of ebusiness is the opportunity to open new markets.
a) True
b) False
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