The ammonia synthesis reaction represented by N2 + 3H2 2NH3; ΔH = - 22.4 kcal, is
Endothermic
Exothermic
Isothermal
Adiabatic
Correct Answer :
B. Exothermic
Related Questions
Gibbs-Duhem equation
States that n1dμ1 + n2dμ2 + ....njdμj = 0, for a system of definite composition at constant temperature and pressure
Applies only to binary systems
Finds no application in gas-liquid equilibria involved in distillation
None of these
If the pressure on 100 c.c. of air is halved, then its volume (at the same temperature) would be __________ c.c.
100
50
205
200
When dilute aqueous solutions of two salts are mixed, the process is associated with
Decrease in temperature
Increase in temperature
No change in temperature
Change in temperature which is a function of composition
As the time is passing, entropy of the universe
Is increasing
Is decreasing
Remain constant
Data insufficient, can't be predicted
At 60° C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60° C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole fractions of methanol are 0.1686 and 0.5714 respectively. Activity co-efficient of methanol is
1.572
1.9398
3.389
4.238
Dryness fraction of wet steam is defined as the ratio of mass of vapour in the mixture to the mass of mixture __________ calorimeter is not used for measuring the dryness fraction of steam.
Bomb
Separating
Bucket
Throttling
Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system?
Expansion valve
Condenser
Refrigerator
Compressor
An ideal gas is taken around the cycle ABCA as shown in P-V diagram below: The work done by the gas during the cycle is equal to
12 P1V1
6 P1 V1
3 P1V1
P1 V1
The co-efficient of performance (COP) of a refrigerating system, which is its index of performance, is defined as the ratio of useful refrigeration to the net work. The units of __________ and COP are the same.
Kinematic viscosity
Work
Temperature
None of these
Van Laar equation deals with the activity coefficients in
Binary solutions
Ternary solutions
Azeotropic mixture only
None of these
Which of the following is not affected by temperature changes?
Fugacity
Activity co-efficient
Free energy
None of these
Work done is a
Property of the system
Path function
Point function
State description of a system
Pick out the correct statement.
Compression ratio of an Otto engine is comparatively higher than a diesel engine
Efficiency of an Otto engine is higher than that of a diesel engine for the same compression ratio
Otto engine efficiency decreases with the rise in compression ratio, due to decrease in work produced per quantity of heat
Diesel engine normally operates at lower compression ratio than an Otto engine for an equal output of work
Kopp's rule is used to calculate the heat capacity of
Solids
Liquids
Gases
All (A), (B) & (C)
If an ideal solution is formed by mixing two pure liquids in any proportion, then the __________ of mixing is zero
Enthalpy
Volume
Both 'a' & 'b'
Neither 'a' nor 'b'
The equation Tds = dE - PdV applies to
Single phase fluid of varying composition
Single phase fluid of constant composition
Open as well as closed systems
Both (B) and (C)
Pick out the wrong statement.
A closed system does not permit exchange of mass with its surroundings but may permit exchange of energy.
An open system permits exchange of both mass and energy with its surroundings
The term microstate is used to characterise an individual, whereas macro-state is used to designate a group of micro-states with common characteristics
None of the above
With increase in reduced temperature, the fugacity co-efficient of a gas at constant reduced pressure
Increases
Decreases
Remain same
Decreases linearly
Which of the following processes cannot be made reversible even under ideal condition of operation?
Free expansion of a gas
Compression of air in a compressor
Expansion of steam in a turbine
All (A), (B) & (C)
Chemical potential is a/an
Extensive property
Intensive property
Force which drives the chemical system to equilibrium
Both (B) and (C)
If different processes are used to bring about the same chemical reaction, the enthalpy change is same for all of them. This is __________ law.
Hess's
Kirchoff's
Lavoisier and Laplace
None of these
Consider the reaction, C + O2 CO2; ΔH = - 94 kcal. What will be the value of ΔH for the reaction CO2 → C + O2?
-94 kcal
+94 kcal
> 94 kcal
< -94 kcal
Degree of freedom of a system consisting of a gaseous mixture of H2 and NH3 will be
0
1
2
3
In a reversible chemical reaction (where, Δx = number of moles of products-number of moles of reactants)
Addition of inert gas favours the forward reaction, when Δx is positive
Pressure has no effect on equilibrium, when Δn = 0
Addition of inert gas has no effect on the equilibrium constant at constant volume for any value of Δx (+ ve, - ve) or zero)
All 'a', 'b' & 'c'
On opening the door of an operating refrigerator kept in a closed room, the temperature of the room will
Increase
Decrease
Remain same
Increase in summer and will decrease in winter
Pick out the wrong statement
Phase rule variables are intensive properties
Heat and work are both state function
The work done by expansion of a gas in vacuum is zero
CP and CV are state function
__________ functions are exemplified by heat and work.
Path
Point
State
None of these
Fugacity and pressure are numerically not equal for the gases
At low temperature and high pressure
At standard state
Both (A) and (B)
In ideal state
Absolute zero temperature signifies the
Minimum temperature attainable
Temperature of the heat reservoir to which a Carnot engine rejects all the heat that is taken in
Temperature of the heat reservoir to which a Carnot engine rejects no heat
None of these
Translational kinetic energy of molecules of an ideal gas is proportional to (where, T = absolute temperature of the gas)
T
√T
T2
1/√T