Thermodynamics for Chemical Mcqs - Set 17

1)   Heat pump_______________________?

a. Accomplishes only space heating in winter
b. Accomplishes only space cooling in summer
c. Accomplishes both A. and B
d. Works on Carnot cycle
Answer  Explanation 

ANSWER: Accomplishes both A. and B

Explanation:
No explanation is available for this question!


2)   For an ideal solution, the value of activity co-efficient is______________________?

a. 0
b. 1
c. < 1
d. > 1
Answer  Explanation 

ANSWER: 1

Explanation:
No explanation is available for this question!


3)   Isentropic process means a constant _____________________ process ?

a. Enthalpy
b. Pressure
c. Entropy
d. None of these
Answer  Explanation 

ANSWER: Entropy

Explanation:
No explanation is available for this question!


4)   Entropy is a/an___________________?

a. State function
b. Macroscopic property
c. Extensive property
d. None of these
Answer  Explanation 

ANSWER: None of these

Explanation:
No explanation is available for this question!


5)   If an ideal solution is formed by mixing two pure liquids in any proportion, then the ___________________ of mixing is zero?

a. Enthalpy
b. Volume
c. Both A. & B.
d. Neither A nor B
Answer  Explanation 

ANSWER: Both A. & B.

Explanation:
No explanation is available for this question!


6)   The temperature at which both liquid and gas phases are identical, is called the _____________ point?

a. Critical
b. Triple
c. Freezing
d. Boiling
Answer  Explanation 

ANSWER: Critical

Explanation:
No explanation is available for this question!


7)   Tea kept in a thermos flask is vigorously shaken. If the tea is considered as a system, then its temperature will_________________?

a. Increase
b. Decrease
c. Remain unchanged
d. First fall and then rise
Answer  Explanation 

ANSWER: Increase

Explanation:
No explanation is available for this question!


8)   Joule-Thomson co-efficient for a perfect gas is_____________________?

a. Zero
b. Positive
c. Negative
d. None of these
Answer  Explanation 

ANSWER: Zero

Explanation:
No explanation is available for this question!


9)   Grams of butane (C4H10) formed by the liquefaction of 448 litres of the gas (measured at (STP) would be__________________?

a. 580
b. 640
c. 1160
d. Data insufficient; can’t be computed
Answer  Explanation 

ANSWER: 1160

Explanation:
No explanation is available for this question!


10)   In the ammonia synthesis reaction, N2 + 3H2 ⇌ 2NH3 + 22.4 kcal, the formation of NH3 will be favoured by___________________?

a. High temperature
b. Low pressure
c. Low temperature only
d. Both low temperature and high pressure
Answer  Explanation 

ANSWER: Both low temperature and high pressure

Explanation:
No explanation is available for this question!


11)   What is the number of degree of freedom for a system of two miscible non-reacting species in vapor-liquid equilibrium forming an azeotrope ?

a. 0
b. 2
c. 1
d. 3
Answer  Explanation 

ANSWER: 1

Explanation:
No explanation is available for this question!


12)   What is the value of ln y (where y = activity co-efficient) for ideal gases ?

a. Zero
b. Unity
c. Infinity
d. Negative
Answer  Explanation 

ANSWER: Zero

Explanation:
No explanation is available for this question!


13)   Change of heat content when one mole of compound is burnt in oxygen at constant pressure is called the__________________?

a. Calorific value
b. Heat of reaction
c. Heat of combustion
d. Heat of formation
Answer  Explanation 

ANSWER: Heat of combustion

Explanation:
No explanation is available for this question!


14)   For a single component two phase mixture, the number of independent variable properties are_________________?

a. Two
b. One
c. Zero
d. Three
Answer  Explanation 

ANSWER: One

Explanation:
No explanation is available for this question!


15)   When a gas in a vessel expands, its internal energy decreases. The process involved is________________?

a. Reversible
b. Irreversible
c. Isothermal
d. Adiabatic
Answer  Explanation 

ANSWER: Reversible

Explanation:
No explanation is available for this question!


16)   The Joule-Thomson co-efficient is defined as (∂T/∂P)H. Its value at the inversion point is__________________?

a.
b. 1
c. 0
d. -ve
Answer  Explanation 

ANSWER: 0

Explanation:
No explanation is available for this question!


17)   Enthalpy ‘H’ is defined as___________________?

a. H = E – PV
b. H = F – TS
c. H – E = PV
d. None of these
Answer  Explanation 

ANSWER: H – E = PV

Explanation:
No explanation is available for this question!


18)   A closed system is cooled reversibly from 100°C to 50°C. If no work is done on the system________________?

a. its internal energy (U) decreases and its entropy (S) increases
b. U and S both decreases
c. U decreases but S is constant
d. U is constant but S decreases
Answer  Explanation 

ANSWER: U and S both decreases

Explanation:
No explanation is available for this question!


19)   The chemical potential for a pure substance is ____________ its partial molal free energy?

a. More than
b. Less than
c. Equal to
d. Not related to
Answer  Explanation 

ANSWER: Equal to

Explanation:
No explanation is available for this question!


20)   The number of degrees of freedom at the triple point of water is__________________?

a. 0
b. 1
c. 2
d. 3
Answer  Explanation 

ANSWER: 0

Explanation:
No explanation is available for this question!


21)   In a turbine, the fluid expands almost_________________?

a. Isothermally
b. Isobarically
c. Adiabatically
d. None of these
Answer  Explanation 

ANSWER: Adiabatically

Explanation:
No explanation is available for this question!


22)   Compressibility factor (i.e., the ratio of actual volume of gas to the volume predicted by ideal gas law) for all gases are_______________?

a. Always greater than one
b. Same at the same reduced temperature
c. Same at the same reduced pressure
d. Both B. & C
Answer  Explanation 

ANSWER: Both B. & C

Explanation:
No explanation is available for this question!


23)   The temperature at which a real gas obeys the ideal gas laws over a wide range of pressure is called the ____________ temperature?

a. Critical
b. Boyle
c. Inversion
d. Reduced
Answer  Explanation 

ANSWER: Boyle

Explanation:
No explanation is available for this question!


24)   Mollier diagram is a plot of___________________?

a. Temperature vs. enthalpy
b. Temperature vs. enthalpy
c. Entropy vs. enthalpy
d. Temperature vs. internal energy
Answer  Explanation 

ANSWER: Entropy vs. enthalpy

Explanation:
No explanation is available for this question!


25)   At triple point (for one component system), vapour pressure of solid as compared to that of liquid will be________________?

a. More
b. Less
c. Same
d. More or less; depending on the system
Answer  Explanation 

ANSWER: Same

Explanation:
No explanation is available for this question!


26)   Equation which relates pressure, volume and temperature of a gas is called the__________________?

a. Equation of state
b. Gibbs Duhem equation
c. Ideal gas equation
d. None of these
Answer  Explanation 

ANSWER: Equation of state

Explanation:
No explanation is available for this question!


27)   Which of the following is not correct for a reversible adiabatic process ?

a. TVγ-1 = constant
b. p1-γ.TY = constant
c. PVγ = constant
d. None of these
Answer  Explanation 

ANSWER: None of these

Explanation:
No explanation is available for this question!