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This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
1. |
There are 5 tanks connected in series. If the average residence time is 5 sec, first order rate constant is 0.5 sec-1, the initial concentration is 5\(\frac{mol}{m^3},\) then the conversion at the exit of 5th reactor in (\(\frac{mol}{m^3}\)) is ____ |
A. | 0.34 |
B. | 0.51 |
C. | 0.65 |
D. | 0.81 |
Answer» D. 0.81 | |
2. |
The exit age distribution as a function of time is ____ |
A. | E = \(\frac{t^{N-1}}{τ^N}\frac{N^N}{(N-1)!}e^\frac{-tN}{τ}\) |
B. | E = \(\frac{t^{N-1}}{τ^N}\frac{N}{(N-1)!}e^\frac{-tN}{τ}\) |
C. | E = \(\frac{t^N}{τ^N}\frac{N^N}{(N-1)!}e^\frac{-tN}{τ}\) |
D. | E = \(\frac{t^{N-1}}{τ^2}\frac{N^N}{(N-1)!}e^\frac{-tN}{τ}\) |
Answer» B. E = \(\frac{t^{N-1}}{τ^N}\frac{N}{(N-1)!}e^\frac{-tN}{τ}\) | |
3. |
If τ = 5 s, first order rate constant, k = 0.25 sec-1 and the number of tanks, N is 5, then the conversion is ____ |
A. | 67.2% |
B. | 75% |
C. | 33% |
D. | 87.45% |
Answer» B. 75% | |
4. |
If τ2 = 100 and σ2 = 10, the number of tanks necessary to model a real reactor as N ideal tanks in series is ____ |
A. | 1 |
B. | 10 |
C. | 5 |
D. | 100 |
Answer» C. 5 | |
5. |
According to tanks in series model, the spread of the tracer curve is proportional to ____ |
A. | Square of distance from the tracer origin |
B. | Square root of distance from the tracer origin |
C. | Cube of distance from the tracer origin |
D. | Inverse square of distance from the tracer origin |
Answer» C. Cube of distance from the tracer origin | |
6. |
Which of the following correctly represents the Damkohler number for a first order reaction? (Where, τ is the space time) |
A. | k |
B. | τ |
C. | \(\frac{1}{kτ}\) |
D. | k τ |
E. | kb) τc) \(\frac{1}{kτ}\) d) k τ |
Answer» E. kb) τc) \(\frac{1}{kτ}\) d) k τ | |
7. |
For a first order reaction, where k is the first order rate constant, the conversion for N tanks in series is obtained as ____ |
A. | XA = 1-\(\frac{1}{(1+\frac{τk}{N})^N} \) |
B. | XA = 1+\(\frac{1}{(1+\frac{τk}{N})^N} \) |
C. | XA = \(\frac{1}{(1+\frac{τk}{N})^N} \) |
D. | XA = \(\frac{1}{(1+\frac{τk}{N})^N} \)– 1 |
Answer» B. XA = 1+\(\frac{1}{(1+\frac{τk}{N})^N} \) | |
8. |
State true or false.The tank in series model depicts a non – ideal tubular reactor as a series of equal sized CSTRs. |
A. | True |
B. | False |
Answer» B. False | |
9. |
State true or false.The tank in series model is a single parameter model. |
A. | False |
B. | True |
Answer» C. | |
10. |
If τ is the average residence time and σ2 is the standard deviation, then the number of tanks necessary to model a real reactor as N ideal tanks in series is ____ |
A. | N = \(\frac{\tau^2}{σ^2} \) |
B. | N = \(\frac{σ^2}{τ^2} \) |
C. | N = σ2 |
D. | N = \(\frac{1}{τ^2} \) |
Answer» B. N = \(\frac{σ^2}{τ^2} \) | |