Numerical Problems by Mam PDF

Numerical Problems

BT2061: Biochemical Thermodynamics M. Hamsa Priya

M. Hamsa Priya

 

BT2061:Problems

 

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Material Mate rial and Energ Energyy Balan Balance ce

Problem 1

N2  gas is being removed from a high pressure storage tank through a device that removes 1% of the current content of the tank each minute. If 

the tank initially contains 1000 moles of the gas, how much will remain at the end of 20 minutes?

M. Hamsa Priya

 

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Material Mate rial and Energ Energyy Balan Balance ce

Problem 2

As a result of a chemical spill, chloroform is evaporating at the rate of 1 gm/minute into a room that is 6 m   ×   6 m   ×  3 m in size and ventilation rate of 10 m3 /min. a. Compute the steady state concentration of chloroform in the room b. Assuming the air in the room is initially free of chloroform, compute the time necessary for chloroform to reach 95% of the steady state concentration

M. Hamsa Priya

 

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Material Mate rial and Energ Energyy Balan Balance ce

Problem 3

The following reaction occurs in air: 2NO +  O2   → 2NO2

At 20 C the rate of this reaction is ◦

dCNO   = −1.4 × 104 C2NO CO2  for t dt

 

in seconds and concentration in kmol/m3 . The reaction occurs in a constant volume 2-L vessel, and the initial concentration of   NO   is 1 kmol/m3 and that of   O2  is 3 kmol/m3 a. If 0.5 mol of   NO  reacts, how much   NO2  is produced? b. Determine how long it would take for 0.5 mol of   NO  to have reacted.

M. Hamsa Priya

 

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Material Mate rial and Energ Energyy Balan Balance ce

Problem 4

One mole of a gas at a temperature of 25 C and a pressure of 1 bar is to be heated and compressed in a frictionless piston and cylinder to 300 C and 10 bar. Compute the heat and work required along each of the ◦

◦

∗

following paths. Assume gas to be an ideal gas with   CP   =   38  J/(mol K) Path A: Isothermal (constant temperature) compression to 10 bar, then isobaric (constant pressure) heating to 300 C Path B: Isobaric heating to 300 C followed by isothermal compression to 10 bar Path C: A compression in which PVγ  = constant where  where   γ   =   C P  followed ◦

◦

∗

by an isobaric cooling or heating, if necessary to 300 C. ◦

∗ C V 

M. Hamsa Priya

 

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