Discuss in detail what is meant by reactive chemicals and explosives.

Ethanol, C2H6O, is most often blended with gasoline - usually as a 10 percent mix - to create a fuel called gasohol. Ethanol is a renewable resource and ethanol-blended fuels, like gasohol, appear to burn more efficiently in combustion engines. The heat of combustion of ethanol is 326.7 kcal/mol. The heat of combustion of 2-methylhexane, C7H16, is 1.150×103 kcal/mol. How much energy is released during the complete combustion of 324 grams of 2-methylhexane ? kcal Assuming the same efficiency, would 324 grams of ethanol provide more, less, or the same amount of energy as 324 grams of 2-methylhexane?

b. Combustion reactions are exothermic. The heat of reaction for the combustion of pentane, C5H12, is 838.7 kcal/mol. What is the heat of combustion for pentane in kcal/gram? kcal/gram How much heat will be given off if molar quantities of pentane react according to the following equation? C5H12 + 8 O2----------5 CO2 + 6 H2O _____ kcal

Determine the partial pressure of CO2 corresponding the transition between solid phases of Mg(OH)2(S) and magnesite MgCO3(S) in an open system open to CO2. Which solid phase will predominate at a 10-3.5 Atm pressure of CO2? The solubility products of Mg(OH)2 and MgCO3 are 10-10.7 and 10-7.5, respectively. The Henry constant of CO2 is 101.5 Atm·L·mol-1

500 kgmol/h of a gas stream containing 2% of component A is to be purified using gas absorption. The vent from the absorber can contain no more than 0.5 kgmol/h of A. Two scrubbing liquids, P and Q, are available.

a. For liquid Q, m=0.45. How many stages are required in the scrubber for 1.5 times the minimum liquid rate? The incoming Q contains no A. 2

b. For liquid P, m=0.25. If liquid P is used in the scrubber specified in part a, at the same rate as Q is used in part a, what recovery can be achieved? The incoming P contains no A.

c. How would the answer to b change if the incoming P contains 0.1% A?

2500 mol/min of a liquid stream containing 1% component B is to be treated by stripping with air. The incoming air contains 0.01% B, and the liquid leaving the stripper is to contain 0.01% B. The Henry’s law constant is 1.5.

a. What is the minimum required gas rate?

b. If the gas rate is 1.15 times the minimum gas rate, how many theoretical stages are required?

An exhaust stream contains 1250 ppm of a toxic impurity that is to be removed by adsorption into a clean liquid; the absorber vent must contain no more than 15 ppm of the impurity. The Henry’s law constant is 0.5.

a. If the gas rate is 7.40 kmol/h, how many theoretical stages are required, and what liquid rate is required, if the absorber operates at 1.35 times the minimum liquid rate?

b. If the gas rate increases to 8.10 kmol/h but still contains 1250 ppm of the impurity, what will the concentration of the impurity of the scrubber vent be? Use the liquid rate and number of stages from part a.

c. If the gas rate increases to 8.10 kmol/h (with 1250 ppm of the impurity), what liquid rate will be required to reduce the concentration in the absorber vent to 15 ppm using the number of stages determined in part a?

A tray tower provides 10 equilibrium stages for stripping ammonia from a wastewater stream by
using a countercurrent air stream at 1 atm and 300 K. Assume that the inlet water concentration
is 0.2 mole% ammonia, the inlet air does not have ammonia, and 1 SCM (standard cubic meter)
of air is fed to the tower per kilogram of wastewater. Here the equilibrium curve is linear with
m= 1.414.
(a) Estimate the outlet molar concentration in the exit water.
(b) Assuming that the Murphree efficiency for the process is 65%, estimate the number of
real trays required for this process.
(c) How many real trays would be required to achieve ½ of the concentration in (a)?

A water-based slurry of mineral is being filtered under vacuum, with a controlled pressure drop of 50 kPa, through a filter paper of 0.09 m² . The slurry is at 25 kg solids per m³ fluid. Use µ = 9.0 × 10−4 Pa.s and the following data:

V [L]                           t [s]                 

0.5                              19

1                                  41

2                                  95

3                                  178

4                                  280

Calculate the medium resistance, Rm; specific cake resistance, a; and the time to produce 5 liters of filtrate.

referring to the paper  "Recent insights on applications of pullulan in tissue engineering", authored by RS Singh, N Kaur, V Rana, and JF Kennedy. It was published in Carbohydrate Polymers, 2016, 153, 455-462.

Which are the physical traits of pullulan which recommend this polymer for tissue engineering ?

How injured tissues can be repaired with the help of artificially created polymeric scaffolds ?

Please mention few pullulan derivatives and explain why the derivatization was necessary for a particular type of application ?

Which are on your opinion the main challenges related to usage of pullulan in tissue engineering ?

A wet plastic film comprised of a polymer and acetone has to be dried using a hot stream of gas in a steady state process. The wet film contains 3 kg of a non-volatile polymer for every kg of acetone. Along with the input of the wet film, a second input of hot gas stream at 80°C is used for the drying process. Since the gas stream is obtained from a recovery unit, it contains nitrogen and a residual amount of acetone such that its relative saturation is 13%. The drying unit has to be evaluated for a case where 78% of acetone is removed from the wet film and the exit gas stream is at 46°C with a dew point temperature of 39°C.


Assume that only acetone transfers from the film to the gas phase i.e. it is the only condensable. Assume that all gas streams are at 1 atm. For vapor pressure of acetone, Antoine coefficients (A = 7.117, B = 1210.595, C = 229.664) in the textbook should be used and assumed to be valid at all given temperatures.


Solve the material balance and calculate the volume of input gas required per kg of the wet film as well as the relative and absolute saturation of the exit gas stream. Then choose the correct answer.

A sample of cross-linked natural rubber (polyisoprene) is found to have shear modulas G = 217 kPA at 20 C. Deduce N, the number of sub-chains between crosslinks per m^3 and hence the number average degree of polymerization between crosslinks. The chemical structure of polyisoprene. You may take for relative atomic mass C=12 and H=1, and for the density rho=909 kg/m^3. Assume <r^2>i = <r^2>o.

1.Write the complete molecular equation for the reaction of Zn(NO3)2 and KOH. Use the "\piπ" button to enter the equation using the equation format and be sure to include the appropriate states of matter.

2.Write the net ionic equation for the reaction in question 1. Use the "\pi π" button to enter the equation using the equation format and be sure to include the appropriate states of matter.

3.What are the spectator ions in for the reaction in question 1? Use the "\piπ" button to enter the equation using the equation format and be sure to include the appropriate charges on the ions.

4. The reaction in question 1 is run and the precipitate removed via filtration. The filtrate (solution which passes through the filter) is collected. We know that the spectator ions should be present, however, one of the active ions is probably limiting and the other active ion is in excess. How could you test for the presence of zinc(II) ions on the filtrate?

5.For the same experiment in the question above, how would you test for the presence of hydroxide ions in the filtrate? (Keep in mind that testing for pH is not a valid test in this case).

An incompressible liquid flows through a straight horizontal pipe. Friction of the fluid within the pipe causes a small amount of heat to be transferred from the fluid; to compensate, flow work must be done on the fluid to move it through the system (so W(dot)fl is greater than zero.

a) How are V(dot)in and V(dot)out related, where V(dot) is the volumetric flow rate of the liquid? (Remember, fluid is incompressible)

b) How must the pressures of Pin and Pout be related?

Any help is appreciated, I don't understand this at all.

Give 8 differences of Equilibrium (or flash distillation) and Simple batch (or differential distillation)