Reaction Engineering Quiz: How Well Do You Understand Reaction Engineering And Separation Process?

The gas phase reaction, A → B + C, is carried out isothermally in a 20 dm³ well mixed, constant volume batch reactor.  20 moles of pure A is placed in the reactor initially. If the reaction is first order (-r_A=kC_A with k= 0.865 min^-1), calculate the time necessary to reduce the number of moles of A in the reactor to 0.2 mol.

• 144.45 min

• 156.45 min

• 179 min

• 256 min

Reaction rate is NOT influenced by type of reactor used?

• True

• False

The reaction, A→  D, is to be carried out isothermally in a continuous flow reactor.  Calculate the CSTR volume necessary to consume 99% of A when the entering molar flow rate is 5 mol/h, assuming that the reaction rate is second order (-r_A = kC_A²) with k = 3 dm³/mol*h.  The entering volumetric flow rate is 10 dm³/h 

• 0.2 mol/dm3

• 0.3 mol/dm3

• 0.4 mol/dm3

• 0.5 mol/dm3

Choose the INCORRECT crystallographic system from the given option

• Cubic

• Tetragonal

• Cyclonic

• Orthorhombic

Choose the correct answers from the 4 types of crystalline solid

1. Ionic crystals
2. Covalent crystals
3. Molecular crystals
4. Non-metallic crystals

• I, II AND III

• I, II AND IV

• I,III AND IV

• ALL ABOVE

In an exothermic reaction in a reactor, A→ B+Cwas carried out adiabatically. Below are the readings recorded automatically by the reactor,X00.20.40.450.50.60.80.9-r,(mol/dm·min)1.01.675.05.05.05.01.250.91 The entering molar flow rate of A is given as 18 kmol/hr. What are the CSTR volumes necessary to achieve 45% conversion?

• V CSTR = 0.027 dm3

• V CSTR = 1.62 dm3

• V CSTR = 27 dm3

• V CSTR = 1620 dm3

Space time is defined as the time necessary to process one reactor volume of fluid based on entrance condition (volumetric flow rate)

• True

• False

1. Which of the following describes the following crystallographic systems correctly?

 

• A=b=c ; α=β=γ≠90°

• A=b=c ; α=β=γ=90°

• A=b≠c ; α=β=γ≠90°

• A≠b≠c ; α=β=γ≠90°

Saturated solution is defined as solution that is in thermodynamic equilibrium with the solid phase of its solute at a given temperature.

• True

• False

In a specific chemical reaction, a company has used chemical A to produce its products with the following equation,A→ Productswhich happens in a plug flow reactor. The following data shows the data that is acquired in a batch reactor.                           X00.10.40.8-ra(mol/dm^3.s)0.010.050.0080.002It is given that the molar feed of A to the PFR is 2 mol/s. What would be the necessary PFR volume that is required to achieve 80% conversion under the identical conditions as the batch reactor data that is acquired? 

• 195.3 dm3

• 293.3 dm3

• 393.5 dm3

• 413.3 dm3

What will be the unit of the k when the reaction is 4^th-order?

• S^-6

• Dm6/mol2.s

• Dm9/mol3.s

• S^-9

When the concentration of the substance in the air surrounding is high, evaporation process will / be ……

• Faster

• Remain the same

• Slower

• Faster then becomes slower

Your professor found out that when reacting 3 moles of gas A and 2 moles of gas B in a flow reactor at 1600 kPa and 327°C produces 3 moles of gas C. When collecting gas C, your professor was a bit surprise because gas C gives out a very pungent smell. After doing some research, your professor discovered that the pungent smell will be present when the concentration of gas C is 0.055 mol/dm3. Therefore, your professor has set the reactor to turn off when the concentration of gas C reaches 0.055 mol/dm3. However, your professor has told his research assistant to collect the remaining gas A and B to be used in another reaction. As his research assistant, you are required to calculate the concentration of gas A & gas B when the reactor is turned off. In your professor’s report, the reaction is done under inert condition with 30% of mass flow rate of gas A and 70% of gas mixture consisting 20% gas N, 30% gas M and 50% gas B.

• Gas A = 0.0437 mol/dm3 Gas B = 0.1355 mol/dm3

• Gas A = 0.1355 mol/dm3 Gas B = 0.0437 mol/dm3

• Gas A = 0.1142 mol/dm3 Gas B = 0.0549 mol/dm3

• Gas A = 0.0743 mol/dm3 Gas B = 0.1142 mol/dm3

1. As an intern of a startup company, you are required to determine the flow rate of the product leaving a single effect evaporator. You found out that the evaporator concentrates of a 1.2 wt% salt solution entering at 327.0 K (54 °C) to a final concentration which is four times the initial concentration. The steam supplied is saturated at 170 kPa. The vapor space of the evaporator is at 101.325 kPa (1.0 atm abs) and the exit flow rate of the vapor is at 8520 kg/h. Given that the steam economy of the evaporator is 88.5%.
2.  

• Cp = 4.14 kJ/kg.K
• Hv = 2256.9 kJ/kg
• λ = 2216 kJ/kg
• T@170 kPa = 116°C

• 3054 kg/h

• 2763 kg/h

• 2277 kg/h

• 2983 kg/h

1. Salt solution undergoes the process of evaporation in a single effect evaporator. The evaporator concentrates of a 1.6 wt% salt solution entering at 500 kg/h and 327.0 K (54 °C) to a final concentration which is unknown. The steam supplied is saturated at 150 kPa and at 750 kg/h. The vapor space of the evaporator is at 101.325 kPa (1.0 atm abs). After that, the vapor from the evaporator is then flow into a reactor with the help of argon gas where both compositions are equimolar to undergo the process of decomposition.

 The process follows the equation: If the reactor is set to be turned off when the concentration of water vapor is at 0.75 kmol/dm³, determine the concentration of oxygen, O2 that is produce in the reactor. Given the molar mass of H2O is 18 kmol/kg and the volumetric flow rate of the reactor is 16 dm3/h.a. 0.254 kmol/dm3b. 0.561 kmol/dm3c. 0.375 kmol/dm3d. 0.744 kmol/dm3

• 0.254 kmol/dm3

• 0.561 kmol/dm3

• 0.375 kmol/dm3

• 0.744 kmol/dm3

In a continuous single effect evaporator, its mass rate of steam, S is 9645 kg/min meanwhile its latent heat of steam condensation at Ts, is 2343 kJ/kg. Find the value of heat transferred per unit time in,W.  

• 6277.28

• 6277.28 X10^3

• 376637.25

• 376637.25 X10^3

In selected industry, an evaporator is used to concentrate 5500 kg/hr of 30% solution of NaOH. The water enters at 80°C. It requires generating 60% of solids at the end of the process. Pressure that has been used in saturated stream is 169.06kPa meanwhile for the pressure vapour space of evaporator is 12.35kPa. The overall heat transfer coefficient is said to be 1700 W/m^2K and the value of heat transfer rate, q = 3345 J/s Find the value of enthalpy of saturated vapour, Hv (kJ/kg).  

• -98.73

• -167.78

• -103.78

• -123.84

Sodium Hydroxide (NaOH) with negligible boiling point rise is being evaporated in a double effect evaporator using saturated steam at 130°C. Areas are equal among both evaporators. The pressure in the vapour of the second effect is estimated about 43.77kPa. Heat transfer coefficient of the first evaporator is given U1=3350 W/m^2.K and the value of ΔT1=20.06°C. Estimate the value of heat transfer coefficient (U2) and boiling point for the second effect. 

• U2=3289.01 W/m^2.K; 67.93°C

• U2=4055.32 W/m^2.K; 85.06°C

• U2=2100.69 W/m^2.K; 77.95°C

• U2=1566.73 W/m^2.K; 88.63°C

Which of the statements below is true? 

• The maximum conversion for irreversible reaction is equal to one.

• For constant volume in flow reactor, the value of v≠v0.

• The design equation of PBR is FAO(dX/dV)=-rA.

• We can use Levenspeil plot to get the volume of PFR.

Your company ask you to create Plug Flow Reactor (PFR) two in series. It is given the intermediate conversion is 40% and the final conversion is 80%. From the table below, find the value of X and the total volume of the reactor. It is given the volume of the first reactor is 0.633 m^3. Hint; use the Simpson’s three point rule. X0.00.10.20.40.60.70.8FA0/-ra0.651.111.45X4.126.008.02

• X=3.05; Total Volume=2.74 m^3

• X=4.09; Total Volume=3.66 m^3

• X=3.05; Total Volume=1.84 m^3

• X=4.09; Total Volume=9.05 m^3

Which of these is not the characteristic of drying? [SEPRO]

• Water usually removed as a vapor by air

• Removal small amount of water

• Water removed as vapor at its boiling point

• Water can be removed mechanically

Enzymes lower activation energy, and thus increase the rate constant and the speed of the reaction. However, increasing the temperature can also increase the rate of the reaction. Does that mean that at extremely high temperature, enzymes can operate at extreme speed? [RE]

• True

• False

Amanda is in her bedroom with a temperature of 25.7 °C and at atmospheric pressure. She turns on the humidifier in her room and the air now contains water vapor with a partial pressure of 3.52kPa. As she’s a chemical engineering student in UTP, her curiosity leads her to a few questions in her head, please enlighten Amanda by showing her your solutions: [SEPRO]Tables provided: steam tableHumidity, HAns: ___________

1. Amanda is in her bedroom with a temperature of 25.7 °C and at atmospheric pressure. She turns on the humidifier in her room and the air now contains water vapor with a partial pressure of 3.52kPa. As she’s a chemical engineering student in UTP, her curiosity leads her to a few questions in her head, please enlighten Amanda by showing her your solutions: [SEPRO]

Tables provided: steam table Saturation humidity, Ans: ___________ 

Amanda is in her bedroom with a temperature of 25.7 °C and at atmospheric pressure. She turns on the humidifier in her room and the air now contains water vapor with a partial pressure of 3.52kPa. As she’s a chemical engineering student in UTP, her curiosity leads her to a few questions in her head, please enlighten Amanda by showing her your solutions: [SEPRO]Tables provided: steam tablePercentage Humidity,Ans: ___________

1. Amanda is in her bedroom with a temperature of 25.7 °C and at atmospheric pressure. She turns on the humidifier in her room and the air now contains water vapor with a partial pressure of 3.52kPa. As she’s a chemical engineering student in UTP, her curiosity leads her to a few questions in her head, please enlighten Amanda by showing her your solutions: [SEPRO]

Tables provided: steam tablePercentage relative humidity,Ans:___________

Acam and his girlfriend were fresh graduates from UTP. He was offered a job as a junior engineer in his future father in law’s food processing company. The dryer used in the industry is a tray dryer and air drying is used. Warm air entered the dryer with a dry bulb temperature of 65°C and a wet bulb temperature of 25°C to be dried by first cooling to 12°C to condense water vapor and then heating to 23.9° C. However, to marry his girlfriend, his father in law wanted him to know more about the drying process and asked him to calculate the following: [SEPRO]Tables provided: Humidity chartvH = (2.83E-3+4.56E-3H) T m3/kg dry aircS = 1.005 +1.88 HkJ/kg dry air. KHy= cS (T-T0) + H/\0 kJ/kg dry airCalculate the initial humidity and percentage humidity? 

Acam and his girlfriend were fresh graduates from UTP. He was offered a job as a junior engineer in his future father in law’s food processing company. The dryer used in the industry is a tray dryer and air drying is used. Warm air entered the dryer with a dry bulb temperature of 65°C and a wet bulb temperature of 25°C to be dried by first cooling to 12°C to condense water vapor and then heating to 23.9° C. However, to marry his girlfriend, his father in law wanted him to know more about the drying process and asked him to calculate the following: [SEPRO]Tables provided: Humidity chartvH = (2.83E-3+4.56E-3H) T m3/kg dry aircS = 1.005 +1.88 HkJ/kg dry air. KHy= cS (T-T0) + Hλ0 kJ/kg dry airCalculate the final humidity and percentage humidity?

Acam and his girlfriend were fresh graduates from UTP. He was offered a job as a junior engineer in his future father in law’s food processing company. The dryer used in the industry is a tray dryer and air drying is used. Warm air entered the dryer with a dry bulb temperature of 65°C and a wet bulb temperature of 25°C to be dried by first cooling to 12°C to condense water vapor and then heating to 23.9° C. However, to marry his girlfriend, his father in law wanted him to know more about the drying process and asked him to calculate the following: [SEPRO]Tables provided: Humidity chartvH = (2.83E-3+4.56E-3H) T m3/kg dry aircS = 1.005 +1.88 HkJ/kg dry air. KHy= cS (T-T0) + H/\0 kJ/kg dry airCalculate humid volume,vH

Acam and his girlfriend were fresh graduates from UTP. He was offered a job as a junior engineer in his future father in law’s food processing company. The dryer used in the industry is a tray dryer and air drying is used. Warm air entered the dryer with a dry bulb temperature of 65°C and a wet bulb temperature of 25°C to be dried by first cooling to 12°C to condense water vapor and then heating to 23.9° C. However, to marry his girlfriend, his father in law wanted him to know more about the drying process and asked him to calculate the following: [SEPRO]Tables provided: Humidity chartvH = (2.83E-3+4.56E-3H) T m3/kg dry aircS = 1.005 +1.88 HkJ/kg dry air. KHy= cS (T-T0) + H/\0 kJ/kg dry airTotal enthalpy, for initial mixture?

After graduated from UTP, you receive a job offer in an ammonia making company. Nitrogen is obtained from fractional distillation of air and hydrogen from natural gas,CH4 + H2O → CO + 3H2 The process of manufacturing of ammonia is Haber Process as shown below:[RE] N2 (g)+3H2 (g)→2NH3 (g)Simulation of the Haber process is carried out using a mixture of 30% pure Hydrogen gas and 70% air (79% Nitrogen) is charged into a flow reactor in which ammonia is produced. Given the total pressure of the system is 200atm and the temperature is kept constant at 450°C. Set up the stoichiometric table for the system and evaluate the concentration of H2 presents in terms of conversion of 20%.  

After graduated from UTP, you receive a job offer in an ammonia making company. Nitrogen is obtained from fractional distillation of air and hydrogen from natural gas,CH4 + H2O → CO + 3H2 The process of manufacturing of ammonia is Haber Process as shown below:[RE] N2 (g)+3H2 (g)→2NH3 (g)Simulation of the Haber process is carried out using a mixture of 30% pure Hydrogen gas and 70% air (79% Nitrogen) is charged into a flow reactor in which ammonia is produced. Given the total pressure of the system is 200atm and the temperature is kept constant at 450°C. Set up the stoichiometric table for the system and evaluate the concentration of N2 presents in terms of conversion of 20%.  

After graduated from UTP, you receive a job offer in an ammonia making company. Nitrogen is obtained from fractional distillation of air and hydrogen from natural gas,CH4 + H2O → CO + 3H2 The process of manufacturing of ammonia is Haber Process as shown below:[RE] N2 (g)+3H2 (g)→2NH3 (g)Simulation of the Haber process is carried out using a mixture of 30% pure Hydrogen gas and 70% air (79% Nitrogen) is charged into a flow reactor in which ammonia is produced. Given the total pressure of the system is 200atm and the temperature is kept constant at 450°C. Set up the stoichiometric table for the system and evaluate the concentration of NH3 presents in terms of conversion of 20%.  

After graduated from UTP, you receive a job offer in an ammonia making company. Nitrogen is obtained from fractional distillation of air and hydrogen from natural gas,CH4 + H2O → CO + 3H2 The process of manufacturing of ammonia is Haber Process as shown below:[RE] N2 (g)+3H2 (g)→2NH3 (g)Simulation of the Haber process is carried out using a mixture of 30% pure Hydrogen gas and 70% air (79% Nitrogen) is charged into a flow reactor in which ammonia is produced. Given the total pressure of the system is 200atm and the temperature is kept constant at 450°C. Set up the stoichiometric table for the system and evaluate the concentration of inert presents in terms of conversion of 20%.