Chemical Process Calculation Questions and Answers Part-18

1. In a reactor, the feed components are NaOH, H2O and HCl. The mass fractions of these components in feed are 0.3, 0.5, 0.2 respectively. The total amount of feed is 800 Kg. At the product side, the total amount of product is 400 Kg and amount of H2O collected is 300 Kg. The mass ratio of NaOH and HCl is 0.6. Assume that there is no reaction is occurring in the reaction. What is the amount of NaOH present in the feed?
a) 240 Kg
b) 480 Kg
c) 560 Kg
d) 800 Kg

Answer: a
Explanation: Mass fraction = Mass of the interested component / Total mass.

2. In a reactor, the feed components are NaOH, H2O and HCl. The mass fractions of these components in feed are 0.3, 0.5, 0.2 respectively. The total amount of feed is 800 Kg. At the product side, the total amount of product is 400 Kg and amount of H2O collected is 300 Kg. The mass ratio of NaOH and HCl is 0.6. Assume that there is no reaction is occurring in the reaction. What is the amount of HCl present in the feed?
a) 80 Kg
b) 160 Kg
c) 240 Kg
d) 320 Kg

Answer: b
Explanation: Mass fraction = Mass of the interested component / Total mass.

3. In a reactor, the feed components are NaOH, H2O and HCl. The mass fractions of these components in feed are 0.3, 0.5, 0.2 respectively. The total amount of feed is 800 Kg. At the product side, the total amount of product is 400 Kg and amount of H2O collected is 300 Kg. The mass ratio of NaOH and HCl is 0.6. Assume that there is no reaction is occurring in the reaction. What is the amount of H2O present in the feed?
a) 100 Kg
b) 200 Kg
c) 400 Kg
d) 800 Kg

Answer: c
Explanation: Mass fraction = Mass of the interested component / Total mass.

4. In a reactor, the feed components are NaOH, H2O and HCl. The mass fractions of these components in feed are 0.3, 0.5, 0.2 respectively. The total amount of feed is 800 Kg. At the product side, the total amount of product is 400 Kg and amount of H2O collected is 300 Kg. The mass ratio of NaOH and HCl is 0.6. Assume that there is no reaction is occurring in the reaction. What is the amount of NaOH present in the product?
a) 21.5 Kg
b) 31.5 Kg
c) 37.5 Kg
d) 40.5 Kg

Answer: c
Explanation: Mass balance for NaOH.

5. In a reactor, the feed components are NaOH, H2O and HCl. The mass fractions of these components in feed are 0.3, 0.5, 0.2 respectively. The total amount of feed is 800 Kg. At the product side, the total amount of product is 400 Kg and amount of H2O collected is 300 Kg. The mass ratio of NaOH and HCl is 0.6. Assume that there is no reaction is occurring in the reaction. What is the amount of HCl present in the product?
a) 62.5 Kg
b) 56.5 Kg
c) 40.5 Kg
d) 32.5 Kg

Answer: a
Explanation: Mass balance for HCl.

6. In a reactor, the feed components are NaOH, H2O and HCl. The mass fractions of these components in feed are 0.3, 0.5, 0.2 respectively. The total amount of feed is 800 Kg. At the product side, the total amount of product is 400 Kg and amount of H2O collected is 300 Kg. The mass ratio of NaOH and HCl is 0.6. Assume that there is no reaction is occurring in the reaction. How many Kgs of NaOH is there in the reactor?
a) 101.5 Kg
b) 202.5 Kg
c) 303.5 Kg
d) 404.5 Kg

Answer: b
Explanation: Mass balance for NaOH

7. In a reactor, the feed components are NaOH, H2O and HCl. The mass fractions of these components in feed are 0.3, 0.5, 0.2 respectively. The total amount of feed is 800 Kg. At the product side, the total amount of product is 400 Kg and amount of H2O collected is 300 Kg. The mass ratio of NaOH and HCl is 0.6. Assume that there is no reaction is occurring in the reaction. How many Kgs of HCl is there in the reactor?
a) 111.5 Kg
b) 122.5 Kg
c) 133.5 Kg
d) 144.5 Kg

Answer: b
Explanation: Mass balance for HCl.

8. In a reactor, the feed components are NaOH, H2O and HCl. The mass fractions of these components in feed are 0.3, 0.5, 0.2 respectively. The total amount of feed is 800 Kg. At the product side, the total amount of product is 400 Kg and amount of H2O collected is 300 Kg. The mass ratio of NaOH and HCl is 0.6. Assume that there is no reaction is occurring in the reaction. How many Kgs of H2O is there in the reactor?
a) 100 Kg
b) 200 Kg
c) 300 Kg
d) 400 Kg

Answer: a
Explanation: Mass balance for H2O.

9. An aqueous solution with NaOH 10 g/L at the rate is 100 L/min and an organic compound with no NaOH at the rate 50 L/min were put into an extraction machine and produced aqueous solution with NaOH 1 g/L, what is the amount of NaOH in organic compound after extraction?
a) 2 g/L
b) 5 g/L
c) 9 g/L
d) 15 g/L

Answer: c
Explanation: NaOH balance equation, 100(10) + 50(0) = 100(1) + 50(x)

10. To obtain a 100 Kg of 40 % N2 solution, how much nitrogen must be added to a 20% nitrogen solution?
a) 10 Kg
b) 25 Kg
c) 50 Kg
d) 75 Kg

Answer: b
Explanation: Use Both nitrogen and solvent balance