250+ TOP MCQs on Degrees of Freedom Analysis and Answers

Basic Chemical Engineering Multiple Choice Questions & Answers (MCQs) on “Degrees of Freedom Analysis”.

1. What are the degrees of freedom?
a) Total variables in the process
b) Total species in the process
c) Total reactions in the process
d) None of the mentioned

Answer: a
Clarification: Degrees of freedom is the total number of variables involved in the process.

2. What are the total degrees of freedom if the number of species are 5, total streams are 2, stream temperature 2, stream pressure 2 and heat released 1?
a) 1
b) 5
c) 6
d) 12

Answer: d
Clarification: Degrees of freedom = 5 + 2 + 2 + 2 + 1 = 12.

3. What are the total degrees of freedom if the number of species are 8, total streams are 3, stream temperature 3, stream pressure 3 and heat released 1, extent of reaction 2?
a) 8
b) 12
c) 15
d) 17

Answer: d
Clarification: Degrees of freedom = 8 + 3 + 3 + 3 + 1 + 2 = 17.

4. What are the total degrees of freedom if the number of species are 4, total streams are 2, stream temperature 2, stream pressure 1 and heat released 1, extent of reaction 1?
a) 4
b) 7
c) 11
d) 15

Answer: c
Clarification: Degrees of freedom = 4 + 2 + 2 + 1 + 1 + 1 = 11.

5. What are the total degrees of freedom if the number of species are 8, total streams are 4, stream temperature 2, stream pressure 2 and heat released 1, extent of reaction 3?
a) 12
b) 16
c) 20
d) 24

Answer: c
Clarification: Degrees of freedom = 8 + 4 + 2 + 2 + 1 + 3 = 20.

6. In a reactor two stream are entering, one with CH₄ at 10 atm and 27^oC, and another with O2 at 10 atm and 0^oC, producing CO₂, CO, H₂O, and O₂ at 10 atm and 23^oC, what are the total degrees of freedom?
a) 12
b) 16
c) 18
d) 20

Answer: c
Clarification: Total species = 1 + 1 + 4 = 6, total stream flows = 3, stream pressures = 3, stream temperatures = 3, heat released = 1, and extent of reaction = 2, => degrees of freedom = 6 + 3 + 3 + 3 + 1 + 2 = 18.

7. In a reactor two stream are entering, one with H₂ at 10 atm and 27^oC, and another with O₂ at 10 atm and 0^oC, producing H₂O₂, H₂O, and O₂ at 10 atm and 23^oC, what are the total degrees of freedom?
a) 12
b) 17
c) 19
d) 23

Answer: b
Clarification: Total species = 1 + 1 + 3 = 5, total stream flows = 3, stream pressures = 3, stream temperatures = 3, heat released = 1, and extent of reaction = 2, => degrees of freedom = 5 + 3 + 3 + 3 + 1 + 2 = 17.

8. In a reactor two stream are entering, one with N₂ at 10 atm and 27^oC, and another with O2 at 10 atm and 0^oC, producing NO, NO₂, NO₃, and O₂ at 10 atm and 23^oC, what are the total degrees of freedom?
a) 12
b) 17
c) 19
d) 21

Answer: c
Clarification: Total species = 1 + 1 + 4 = 6, total stream flows = 3, stream pressures = 3, stream temperatures = 3, heat released = 1, and extent of reaction = 3, => degrees of freedom = 6 + 3 + 3 + 3 + 1 + 3 = 19.

9. In a reactor two stream are entering, one with S at 10 atm and 27^oC, and another with O₂ at 10 atm and 0^oC, producing SO₂, SO₃, and O₂ at 10 atm and 23^oC, what are the total degrees of freedom?
a) 10
b) 13
c) 15
d) 17

Answer: d
Clarification: Total species = 1 + 1 + 3 = 5, total stream flows = 3, stream pressures = 3, stream temperatures = 3, heat released = 1, and extent of reaction = 2, => degrees of freedom = 5 + 3 + 3 + 3 + 1 + 2 = 17.

10. In a reactor two stream are entering, one with H₂ at 10 atm and 27^oC, and another with O₂ at 10 atm and 0^oC, producing H₂O at 10 atm and 23^oC, what are the total degrees of freedom?
a) 10
b) 14
c) 16
d) 19

Answer: b
Clarification: Total species = 1 + 1 + 1 = 3, total stream flows = 3, stream pressures = 3, stream temperatures = 3, heat released = 1, and extent of reaction = 1, => degrees of freedom = 3 + 3 + 3 + 3 + 1 + 1 = 14.

11. If the reactions are unknown, is it possible to determine the degrees of freedom?
a) Yes
b) No
c) Depends on the type of reaction
d) None of the mentioned

Answer: b
Clarification: For degrees of freedom calculation, number of species are required for which the reactions should be known.

12. In a reactor two stream are entering, one with CH₄ at 10 atm and 27^oC, and another with O₂ at 10 atm and 0^oC, producing CO₂ and H₂O at 10 atm and 23^oC, what are the total degrees of freedom?
a) 10
b) 12
c) 15
d) 17

Answer: c
Clarification: Total species = 1 + 1 + 2 = 4, total stream flows = 3, stream pressures = 3, stream temperatures = 3, heat released = 1, and extent of reaction = 1, => degrees of freedom = 4 + 3 + 3 + 3 + 1 + 1 = 15.

13. In a reactor two stream are entering, one with C₆H₆ at 10 atm and 27^oC, and another with H₂ at 10 atm and 0^oC, producing C₆H₁₂ and H₂ at 10 atm and 23^oC, what are the total degrees of freedom?
a) 10
b) 15
c) 20
d) 23

Answer: b
Clarification: Total species = 1 + 1 + 2 = 4, total stream flows = 3, stream pressures = 3, stream temperatures = 3, heat released = 1, and extent of reaction = 1, => degrees of freedom = 4 + 3 + 3 + 3 + 1 + 1 = 15.

14. In a reactor two stream are entering, one with C₆H₆ at 10 atm and 27^oC, and another with H₂ at 10 atm and 0^oC, producing C₆H₆, C₆H₁₂, and H₂ at 10 atm and 23^oC, what are the total degrees of freedom?
a) 10
b) 12
c) 15
d) 16

Answer: d
Clarification: Total species = 1 + 1 + 3 = 5, total stream flows = 3, stream pressures = 3, stream temperatures = 3, heat released = 1, and extent of reaction = 1, => degrees of freedom = 5 + 3 + 3 + 3 + 1 + 1 = 16.

15. In a reactor two stream are entering, one with CO₂ at 10 atm and 27^oC, and another with H₂O at 10 atm and 0^oC, producing CH₄, CO₂, H₂O, and O₂ at 10 atm and 23^oC, what are the total degrees of freedom?
a) 10
b) 15
c) 17
d) 21

Answer: c
Clarification: Total species = 1 + 1 + 4 = 6, total stream flows = 3, stream pressures = 3, stream temperatures = 3, heat released = 1, and extent of reaction = 1, => degrees of freedom = 6 + 3 + 3 + 3 + 1 + 1 = 17.