Chemical Engineering Interview Questions and Answers for freshers on “Accounting for Chemical Reactions in Material Balances”.
1. The general material balance equation for reactive system is Accumulation = Input + Generation – x, what is x?
a) Consumption – Output
b) Consumption + Output
c) Output – Consumption
d) None of the mentioned
Answer: b
Clarification: Accumulation = Input – Output + Generation – Consumption, => x = Consumption + Output.
2. In a system if, Accumulation = Input – Output + Generation – Consumption, where all the four terms are distinct and non-zero, then the system is which of the following?
a) Steady-state
b) Closed
c) Non-reactive
d) None of the mentioned
Answer: d
Clarification: As the formula involves input and output it is an open system, and also as it involves generation and consumption the system is reactive, and since the input is not equal to output so the system is unsteady-state, and the answer is d.
3. In a system if, Accumulation = Generation – Consumption, where both the terms are distinct and non-zero, then the system is which of the following?
a) Steady-state
b) Closed
c) Non-reactive
d) None of the mentioned
Answer: b
Clarification: As the formula does not involve input and output it is a closed system.
4. In a system if, Accumulation = Input – Output, where both the terms are distinct and non-zero, then the system is which of the following?
a) Steady-state
b) Closed
c) Non-reactive
d) None of the mentioned
Answer: c
Clarification: As the formula does not involve generation and consumption it is a non-reactive system.
5. In a steady-state reactive system, NaOH and HCl are supplied to the system both at the rate of 100 mole/min, then what is the rate of NaCl produced?
a) 100 mole/min
b) 200 mole/min
c) 300 mole/min
d) 400 mole/min
Answer: b
Clarification: As the system is in steady-state, rate of product = rate of feed, => rate of NaCl = 100 + 100 = 200 mole/min.
6. In a steady-state reactive system, 1 molar each of NaOH and HCl are supplied to the system both at the rate of 100 L/min, then what is the amount of NaCl produced?
a) 1 molar
b) 2 molar
c) 3 molar
d) 4 molar
Answer: a
Clarification: The balanced reaction of the system is NaOH + HCl -> NaCl + H2O, => amount of NaCl = amount of HCl = amount of NaOH = 1 molar.
7. In a steady-state reactive system, NaCl and H2CO3 are supplied to the system at the rate of 200 L/min and 100 L/min respectively, what is the rate at which Na2CO3 is produced?
a) 100 L/min
b) 200 L/min
c) 300 L/min
d) 400 L/min
Answer: c
Clarification: As the system is in steady state, => rate of product = rate of feed, => rate of Na2CO3 = 200 + 100 = 300 L/min.
8. In a steady-state reactive system, 2 molar NaCl and 1 molar H2CO3 are supplied to the system both at the rate of 100 mole/min, then how much Na2CO3 produced?
a) 1 molar
b) 2 molar
c) 3 molar
d) 4 molar
Answer: a
Clarification: The balanced reaction of the system is 2NaCl + H2CO3 -> Na2CO3 + 2HCl, => amount of Na2CO3 = 1 molar.
9. In a steady-state reactive system, 5 molar CH4 and 5 molar O2 are supplied to the system, then what is the amount of CO2 produced?
a) 2.5 molar
b) 5 molar
c) 7.5 molar
d) 10 molar