STUPIDSID
1(a)
A staturated solution of salicylic acid (HOC6H4COOH) is methanol contain 64 kg salicylic acid per 100 kg methanol at 298 K. Find the composition in (i) weight % and ii) mol e %.
4 M
1(b)
A waste acid from a nitrating process contains 21% HNO3, 55% H2SO4 and 24% water by weight. This acid is concentrated to a mixture containing 28% HNO3, 62%H2SO2 by addition of sulfuric acid containing 93% H2SO4 and nitric acid containing 90% HNO3. Calculate the weight of spent acid, concentrated sulfric acid and concentrated nitric acid that must be combined to obtain 1000 kg of desired mixed acid.
8 M
2(a)
A solution of sodium chloride in water contains 20% NaC1 (by weight) at 333 K. The density of the solution is 1.127 kg/L Find:
i) Molartiy
ii) Normality and
iii) Molality of the solution.
i) Molartiy
ii) Normality and
iii) Molality of the solution.
4 M
2(b)
An aqueous solution of Na2CO3 contain 15% carbonate by weight. 80% of the carbonte recovered as Na2 CO3. 10H2O by evaporation of water and subsequent cooling to 278 K. The solubility of Na2CO3 at 278 K is 9.0% (by weight). On the basis of 100 kg of solution treated, determine the following:
i) The quantity of crystal formed
ii) The amount of water evaporated.
i) The quantity of crystal formed
ii) The amount of water evaporated.
8 M
3(a)
A feed containing 60 role % A, 30 mole % B and 10 mole % inerts enters a reactor. The product stream leaving the reactor if found to contain 2 mode % A. Reaction taking place is 2A+B→C. Find the percentage of original A getting converted to C.
6 M
3(b)
The heat capacity of carbon dioxide is given by the following relation:
Cp=26.540+42.454×10-3-14.298T×10-6T2; where Cp is in kJ/kmol K and T is in K :
i) How much heat is required to heat 1 kg of CO 2 from 300 K to 1000 K?
ii) Obtain the relation expressing the heat capacity in keal/ kmol°C and tempreature in°C.
Cp=26.540+42.454×10-3-14.298T×10-6T2; where Cp is in kJ/kmol K and T is in K :
i) How much heat is required to heat 1 kg of CO 2 from 300 K to 1000 K?
ii) Obtain the relation expressing the heat capacity in keal/ kmol°C and tempreature in°C.
7 M
4(a)
Ammonia is sythesized according to the following reaction:
\[\frac{1}{2}N_2+\frac{3}{4}H_2\rightarrow NH_3\]
\[\Delta H_{298}^{0}=-46.191kJ.\] The specific heat of the components are represented by \[C_{p}=\alpha +\beta T+\gamma T^2\], where Cp is in J/mol K and the constants α
β and γ are:
Determine the heat reaction:
\[\frac{1}{2}N_2+\frac{3}{4}H_2\rightarrow NH_3\]
\[\Delta H_{298}^{0}=-46.191kJ.\] The specific heat of the components are represented by \[C_{p}=\alpha +\beta T+\gamma T^2\], where Cp is in J/mol K and the constants α
β and γ are:
| Molecules | α | β | γ |
| N2 | 27.31 | 5.2335×10-3 | -4.1868×10-9 |
| H2 | 29.09 | -8.347×10-4 | 2.0139×10-6 |
| NH3 | 25.48 | 36.89×10-3 | -6.305×10-6 |
Determine the heat reaction:
9 M
4(b)
Describe the following terms:
i) Limiting reactant
ii) Excess reactant
iii) Percent excess
iv) Stoichiometric coefficient.
i) Limiting reactant
ii) Excess reactant
iii) Percent excess
iv) Stoichiometric coefficient.
4 M
5(a)
The reaction A→ 2B+C takes place in a catalytic reactor (refer fig.). The reactor effluent is sent to a seprator. The overall conversion of A is 95 %. The product stream from the separator consists of B,C and 0.5% of A entering the separator, while the recycle stream consists of the reminder of the unreacted A and 1% B entering the separator. Calculate the following:
1) The single pass conversion of A in the reactor
2) The molar ratio of recycle to feed
!mage
1) The single pass conversion of A in the reactor
2) The molar ratio of recycle to feed
!mage
7 M
5(b)
Write short notes on the following:
1) Dry bulb temperature
2) Wet bulb temperature
3) Dew point.
1) Dry bulb temperature
2) Wet bulb temperature
3) Dew point.
6 M
6(a)
The gas mixture containing carbon disulphide vapour (CS2) at a temperature of 300 K ans pressure of 100 kPa has percentage saturation of 70. Calculate the temperature to which gas must be cooled at constant pressure so as to condenses 40% of CS2 present in it. Data Given:
Vapor pressure of CS2 at 300 K : 52.662 kPa
Vapor pressure of CS2 at 287 K : 31.997 kPa
Vapor pressure of CS2 at 288 K : 33.33 kPa.
Vapor pressure of CS2 at 300 K : 52.662 kPa
Vapor pressure of CS2 at 287 K : 31.997 kPa
Vapor pressure of CS2 at 288 K : 33.33 kPa.
8 M
6(b)
Define realtive humidity and percentage humidity and derive a relation between them.
5 M
7(a)
A furnace is fired with fuel oil. The orsat analysis of the flue gases (by volume ) is CO2 : 10.6%,
O2 : 6% N2 : 83.4%.Calculate the percentage excess air and find the C : H ratio in the fuel oil, assuming that the fuel does not contain nitrogen.
O2 : 6% N2 : 83.4%.Calculate the percentage excess air and find the C : H ratio in the fuel oil, assuming that the fuel does not contain nitrogen.
8 M
7(b)
The gross calorific value of liquid acetone at 298 K is 1791.21 kJ/mol. Find its net calorific value using latent heat of water at 298 K.
4 M
8(a)
Define:
i) Adiabatic flame temperature
ii) HCV
iii) NCV. Is it any difference in the actual and calculated theoretically adibatic flame temperature?
i) Adiabatic flame temperature
ii) HCV
iii) NCV. Is it any difference in the actual and calculated theoretically adibatic flame temperature?
6 M
8(b)
Calculate the NCV at 298 K at a sample of fuel oil having C/H ratio 9.33 (by weight) and containing sulfur to extent of 1.3% by weight Data given: GCV of the fuel oil at 298 K= 41785 kJ/kg Latent heat of water vapor at 298 K= 2442.5 kJ/kg.
6 M
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