This set of Chemical Process Calculation Multiple Choice Questions & Answers (MCQs) focuses on “Material Balances -IV”.
1. In a chemical process, what are the mass fractions of H2O in the feed and NaOH in the product?
a) 0.50 and 0.50
b) 0.65 and 0.50
c) 0.65 and 0.65
d) 0.50 and 0.95
View Answer
Explanation: The sum of mass fractions ΣωI = 1, and thus the mass fractions for H2O in the feed and NaOH in the product are 0.65 and 0.50, respectively.
2. In a chemical process, if the mass fraction and total mass of the feed and product are known, what is the mass in kg of H2O in the feed and NaOH in the product?
a) 65 and 50
b) 95 and 50
c) 65 and 75
d) 50 and 50
View Answer
Explanation: Using mi = ωI × W, where mi is the mass, ωI is the mass fraction, and W is the total weight, we find the mass of H2O in the feed is 65 kg and NaOH in the product is 75 kg.
3. What is the mass fraction of NaOH in component A in a chemical process?
a) 0.2
b) 0.4
c) 0.6
d) 0.8
View Answer
Explanation: The total mass fractions sum to 1, so the mass fraction of NaOH in component A is calculated as 0.8.
4. What is the mass fraction of H2O in component A in a chemical process?
a) 0.2
b) 0.4
c) 0.6
d) 0.8
View Answer
Explanation: The total mass fractions sum to 1, so the mass fraction of H2O in component A is determined to be 0.2.
5. Two tanks contain different concentrations of O2. Tank A has 90% O2, and Tank B has 30% O2. When mixed to form Tank C with 65% O2, what is the ratio of the gas used from Tank A to that used from Tank B?
a) 1.0
b) 1.2
c) 1.4
d) 1.6
View Answer
Explanation: The ratio of gases used from Tank A to Tank B is calculated to ensure that the final concentration in Tank C reaches 65% O2.
6. If Tank A contains 100 moles, how many moles of gas are used from Tank B to achieve a final concentration of 65% O2 in Tank C?
a) 51.4
b) 61.4
c) 71.4
d) 81.6
View Answer
Explanation: Using the ratio of gases from Tank A and Tank B, the required moles from Tank B are calculated as 71.4 moles when Tank A contains 100 moles.
7. If Tank A contains 100 moles, how many total moles of gas are there in Tank C after mixing with Tank B to reach 65% O2?
a) 151.4
b) 161.4
c) 171.4
d) 181.6
View Answer
Explanation: The total moles in Tank C is the sum of moles from Tanks A and B, calculated to be 171.4 moles when Tank A contains 100 moles.
8. The number of variables whose values are unknown minus the number of independent equation is degree of freedom,
The above given statement is
a) True
b) False
c) It is not the definition of degrees of freedom
d) None of the mentioned
View Answer
Explanation: The number of variables whose values are unknown minus the number of independent equation is degree of freedom.
9. Concept of material balance based upon?
a) Conservation of mass
b) Conservation of energy
c) Conservation of momentum
d) Conservation of Volume
View Answer
Explanation: Material balance is based on conservation of mass.
10. Closed systems have ________ type of boundary wall.
a) Impermeable
b) Permeable
c) Rigid
d) None of the mentioned
View Answer
Explanation: The matter is not allowed to cross the boundary wall of a closed system.
Sanfoundry Global Education & Learning Series – Chemical Process Calculation.
To practice all areas of Chemical Process Calculation, here is complete set of 1000+ Multiple Choice Questions and Answers.
