Chemical Engineering online test on “Liquids and Gases in Equilibrium with Solids”.
1. What is the fraction of a gas in a system at partial pressure 1 mm Hg, if the 0.2 fraction of the same gas is at partial pressure 2 mm Hg and 0.3 fraction at partial pressure 3 mm Hg (Use Freundlich Isotherm)?
a) 0.1
b) 0.2
c) 0.3
d) 0.4
Answer: a
Clarification: y1/y2 = (p1/p2)n, => 0.2/0.3 = (2/3)n => n = 1, => 0.2 = k*21 = k = 0.1, => y = 0.1*11 = 0.1.
2. What is the fraction of a gas in a system at partial pressure 2 mm Hg, if the 0.2 fraction of the same gas is at partial pressure 8 mm Hg and 0.3 fraction at partial pressure 18 mm Hg (Use Freundlich Isotherm)?
a) 0.0125
b) 0.0250
c) 0.0375
d) 0.0450
Answer: a
Clarification: y1/y2 = (p1/p2)n, => 0.2/0.3 = (8/18)n => n = 2, => 0.2 = k*82 = k = 0.2/64, => y = 0.2/64*22 = 0.0125.
3. What is the fraction of a gas in a system at partial pressure 1 atm, if the 0.1 fraction of the same gas is at partial pressure 2 atm and 0.2 fraction at partial pressure 4 atm (Use Freundlich Isotherm)?
a) 0.01
b) 0.03
c) 0.05
d) 0.08
Answer: c
Clarification: y1/y2 = (p1/p2)n, => 0.1/0.2 = (2/4)n => n = 1, => 0.1 = k*21 = k = 0.1/2, => y = 0.1/2 = 0.05.
4. What is the fraction of a gas in a system at partial pressure 1 atm, if the 0.2 fraction of the same gas is at partial pressure 4 atm and 0.4 fraction at partial pressure 8 atm (Use Freundlich Isotherm)?
a) 0.1
b) 0.2
c) 0.4
d) 0.5
Answer: d
Clarification: y1/y2 = (p1/p2)n, => 0.2/0.4 = (4/8)n => n = 1, => 0.2 = k*41 = k = 0.2/4, => y = 0.2/4*1 = 0.05.
5. What is the fraction of a gas in a system at partial pressure 3 atm, if the 0.2 fraction of the same gas is at partial pressure 4 atm and 0.3 fraction at partial pressure 6 atm (Use Freundlich Isotherm)?
a) 0.1
b) 0.15
c) 0.2
d) 0.25
Answer: b
Clarification: y1/y2 = (p1/p2)n, => 0.2/0.3 = (4/6)n => n = 1, => 0.2 = k*41 = k = 0.2/4, => y = 0.2/4*31 = 0.15.
6. Which of the following is called for the adsorbing the molecules?
a) Adsorbate
b) Adsorbent
c) Absobate
d) None of the mentioned
Answer: b
Clarification: The one which adsorbs the molecules is called the adsorbent.
7. Which of the following adsorbs on the adsorbing surface?
a) Adsorbate
b) Adsorbent
c) Absobate
d) None of the mentioned
Answer: a
Clarification: Adsorbate adsorbs on the adsorbent.
8. Which of the following is called for the curves following isothermal adsorbtion?
a) Adsorbtion isotherm
b) Adsorbate isotherm
c) Adsorbent isotherm
d) Absorbent isotherm
Answer: a
Clarification: The curves for isothermal adsorbtion are called adsorbtion isotherms.
9. Which of the following is the property of adsorbtion isotherm?
a) Linear
b) Decreasing
c) Monotonous
d) None of the mentioned
Answer: c
Clarification: Since the adsorbtion isotherms are always increasing they are monotonous.
10. Which of the following satisfies the first derivative of adsorbtion isotherms?
a) Greater than 1
b) Less than 1
c) Equal to 1
d) Cannot say
Answer: a
Clarification: Since adsorbtion isotherms are always increasing, so their first derivative are always increasing.