Most important Chemical Engineering MCQs with answers for chemical engineers jobs test preparation online.
Chemical Engineering MCQs
Maximum heat transfer rate can be expected in case of:
A. Laminar flow
B. Co-current flow
C. Turbulent flow
D. Heat flow rate is independent
Baffles are provided in heat exchangers to:
A. Remove dirt
B. Increase heat transfer rate
C. Reduce vibrations
D. Reduce heat transfer rate
The molecules of a liquid which is in equilibrium with its vapor at its boiling point on an average have equal _____ in the two phases:
A. Potential energy
B. Intermolecular forces
C. Kinetic energy
D. Total energy
At a temperature of 0°K, the molecules of a gas have only _____ energy:
A. Rotational
B. Vibrational
C. Translational
D. None of these
On mixing 56 gm of CaO with 63 gm of HNO3, the amount of Ca(NO3)2 formed is ___ gm:
A. 82
B. 164
C. 41
D. 8.2
Atmospheric pressure corresponds to a hydrostatic head of:
A. 13.6 cms of Hg
B. 34 ft ofH2O
C. 1 metre of H2O
D. 13.6 metres of Hg
Clausius Clapeyron equation applies to the ___ process:
A. Sublimation
B. Melting
C. Vaporisation
D. All A., B. & C.
___ chart is a graph related to Antoine equation:
A. Ostwald
B. Cox
C. Mollier’s
D. Enthalpy-concentration
If a solution of eutectic composition is cooled, ____ reaching the eutectic temperature:
A. The solvent begins to freeze out even before
B. It will undergo no change until
C. It will not solidify even on
D. None of these
The heat of solution depends upon the:
A. Nature of solvent
B. Concentration of solution
C. Nature of solute
D. All A., B. & C.
pH value of a solution containing equal concentration of hydroxyl and hydrogen ions will be:
A. 0
B. 10
C. 7
D. 14
In a chemical process, the recycle stream is purged for:
A. Increasing the product yield
B. Enriching the product
C. Limiting the inerts
D. Heat conservation
Which of the following gases will have the- highest kinetic energy per mole at the same pressure & temperature:
A. Chlorine
B. Nitrogen
C. Ethane
D. All the gases will have the same KE
If 1 Nm3 of O2 contains ‘N’ number of molecules, then number of molecules in 2Nm3 of SO2 will be:
A. N
B. N/2
C. 2N
D. 4N
The total number of atoms in 8.5 gm of NH3 is ___× 1023:
A. 9.03
B. 3.01
C. 1.204
D. 6.02
As per Kirchhoff s equation, the heat of reaction is affected by the:
A. Pressure
B. Volume
C. Temperature
D. Molecularity
______ equation gives the effect of temperature on heat of reaction:
A. Kirchoff’s
B. Maxwell’s
C. Antoine
D. Kistyakowsky
Addition of a non-volatile solute to a pure solvent:
A. Increases its freezing point
B. Increases its boiling point
C. Decreases its freezing point
D. Both B. and C.
1 torr is equal to ____ mm Hg column:
A. 1
B. 0.1
C. 10
D. 1000
The quantity of heat required to evaporate 1 kg of a saturated liquid is called:
A. Specific heat
B. 1 Kcal
C. Sensible heat
D. Latent heat
Which of the following is not a colligative property:
A. Osmotic pressure
B. Depression of freezing point
C. Lowering of vapor pressure
D. None of these
Total energy at a point comprises of _____ energy:
A. Potential & kinetic
B. Pressure
C. Internal
D. All A., B. & C.
The temperature of a gas in a closed container is 27° C. If the temperature of the gas is increased to 300° C, then the pressure exerted is:
A. Doubled
B. Halved
C. Trebled
D. Unpredictable
Hess’s law of constant heat summation is based on conservation of mass. It deals with:
A. Equilibrium constant
B. Reaction rate
C. Changes in heat of reaction
D. None of these
Number of gm moles of solute dissolved in one liter of a solution is called its:
A. Equivalent weight
B. Molarity
C. Molality
D. Normality
A gaseous mixture contains 14 kg of N2, 16 kg of O2 and 17 kg of NH3. The mole fraction of oxygen is:
A. 0.16
B. 0.33
C. 0.66
D. 0.47
Vapor pressure of a solution is proportional to (where, Sv and St are mole fraction of solvent and solute respectively):
A. Sv
B. 1/St
C. St
D. 1/Sv
The value of gas constant ‘R’ is ______ kcal/kg.mole.°C:
A. 2.79
B. 1.987
C. 3.99
D. None of these
In a binary liquid system, the composition expressed as _____ is independent of the temperature & pressure:
A. Kg of solute/kg of solvent
B. Kg-mole of solute/kg-mole of solvent
C. Kg-mole of solute/1000 kg of solvent
D. All A., B. & C.
Unit of mass velocity is:
A. kg/m.hr
B. kg/m2.hr
C. kg/hr
D. kg/m2
Elements in a periodic table are arranged in order of their:
A. Atomic number
B. Mass number
C. Atomic weight
D. Metallic characteristics
The most convenient way of expressing solution concentration is in terms of:
A. Mole fraction
B. Normality
C. Molality
D. Molarity
Disappearance of snow in subzero weather exemplifies the process of:
A. Evaporation
B. Sublimation
C. Vaporisation
D. Melting
Volume occupied by one gm mole of a gas at S.T.P. is:
A. 22.4 litres
B. 22400 litres
C. 22.4 c.c
D. 359 litres
Which of the following has the least (almost negligible) effect on the solubility of a solute in a solvent:
A. Temperature
B. Nature of solute
C. Pressure
D. Nature of solvent
According to the kinetic theory, the thermal conductivity of a monatomic gas is proportional to:
A. T
B. T0.5
C. T1.5
D. T2
Sodium ____ has inverted solubility curve i.e. its solubility increases with the lowering of temperature:
A. Carbonate (monohydrate)
B. Chloride
C. Thiosulphate
D. Bisulphite
1 Kcal/kg. °C is equivalent to _____ BTU/lb. °F:
A. 1
B. 2.42
C. 4.97
D. None of these
In _____ process, ions of salts react with water to produce acidity or alkalinity:
A. Hydration
B. Hydrolysis
C. Electrolysis
D. Dialysis
The value of (Cp – Cv) for a real gas obeying Vander Wall’s equation is:
A. R
B. > R
C. < R
D. 0.5 R
One ‘Therm’ is equivalent to:
A. 105 BTU
B. 105 kcal
C. 109 BTU
D. 109 kcal
Pure oxygen is mixed with air to produce an enriched air containing 50 volume % of oxygen. The ratio of moles of air to oxygen used is:
A. 1.72
B. 0.58
C. 0.5
D. 0.2
How much O2 can be obtained from 90 kg of water:
A. 32 kg
B. 80 kg
C. 64 kg
D. 90 kg
What is the simplest formula of a compound containing 50% of element A (atomic weight = 10) and 50% of element B (atomic weight = 20):
A. AB3
B. A2B3
C. A2B
D. AB2
Which of the following has the smallest least effect on the solubility of a solute into the solvent:
A. Nature of the solute
B. Nature of the solvent
C. Temperature
D. Pressure
Normality of a solution does not change with the increase in the:
A. Pressure
B. Temperature
C. Solute concentration
D. Dilution of the solution
The depression in freezing point of a solution is:
A. Inversely proportional to the mass of solvent
B. Directly proportional to the mole of solute
C. Both A. and B.
D. Neither A. nor B.
At higher temperatures, molal heat capacities for most of the gases (at constant pressure) ____ with increase in temperature:
A. Varies linearly
B. Increases
C. Decreases
D. Does not vary
Which of the following terms of Vander Walls equation of state for a non-ideal gas accounts for intermolecular forces:
A. RT
B. P + (a/V2)
C. (V – b)
D. 1/RT
With increase in the solute concentration, the specific heat of aqueous solutions:
A. Increases
B. Decreases
C. Remains unchanged
D. Either A. or B.; depends on the type of solution
Which of the following is not a unit of kinematic viscosity:
A. Poise
B. Stoke
C. cm2/second
D. None of these
Isotopes are atoms having the same:
A. Mass number
B. Number of neutrons
C. Atomic mass
D. None of these
The heat capacity of most substances is greater for the _______ state:
A. Solid
B. Liquid
C. Gaseous
D. None of these
A sugar solution containing ______ percent sugar is equivalent to 1 Brix:
A. 0.01
B. 0.1
C. 1
D. 10
pH value of a solution containing 1 gm of hydrogen ion per litre will be:
A. 0
B. 1
C. 7
D. 10
Equal masses of CH4 and H2 are mixed in an empty container. The partial pressure of hydrogen in this container expressed as the fraction of total pressure is:
A. 1/9
B. 8/9
C. 1/2
D. 5/9
No cooling occurs, when an ideal gas undergoes unrestrained expansion, because the molecules:
A. Collide without loss of energy
B. Do work equal to loss in kinetic energy
C. Are above the inversion temperature
D. Exert no attractive force on each other
Density of carbon dioxide is _______ kg/Nm3:
A. 44/22400
B. 44/22.4
C. 22.4/44
D. None of these
Molar heat capacity of water in equilibrium with ice at constant pressure is:
A. 0
B. ∞
C. 1
D. None of these
At room temperature, the product [H+] [OH-] in a solution is 10-14 moles/litre. If, [OH-] = 10-6 moles/litre, then the pH of the solution will be:
A. 6
B. 8
C. 10
D. 12
The chemical nature of an element is independent of:
A. Its atomic number
B. The number of protons or electrons present in it
C. The number of neutrons present in it
D. None of these
In general, the specific heats of aqueous solutions ____ with increase in the concentration of the solute:
A. Increase
B. Decrease
C. Remain unchanged
D. None of these
S.T.P. corresponds to:
A. 1 atm. absolute pressure & 15.5°C
B. 760 mm Hg gauge pressure & 15.5°C
C. 760 torr & 0°C
D. 101.325 kPa gauge pressure & 15.5°C
If pH value of a solution is 8, then its pOH value will be:
A. 6
B. 1
C. 7
D. 10
Average molecular weight of air is about:
A. 21
B. 29
C. 23
D. 79
With increase in temperature, the surface tension of water:
A. Increases
B. Decreases
C. Remain constant
D. Increases linearly
Vapor pressure of water at 100°C is about _____ bar:
A. 0.1013
B. 1.013
C. 10.13
D. 101.3
Atomic _____ of an element is a whole number:
A. Weight
B. Number
C. Volume
D. Radius
The latent heat of vaporisation:
A. Decreases with increased temperature
B. Decreases as pressure increases
C. Becomes zero at the critical point
D. All A., B. & C.
Atoms of the same element, but of different masses are called:
A. Isobars
B. Isotones
C. Isotopes
D. None of these
The temperature at which the second Virial co-efficient of a real gas is zero is called the:
A. Eutectic point
B. Boyle temperature
C. Boiling point
D. Critical temperature
Percentage saturation of a vapor bearing gas is always _____ the relative saturation:
A. Higher than
B. Smaller than
C. Equal to
D. Either A. or B.; depends on the system
Size range of the colloids particles is:
A. 5 – 200 milli-microns
B. 50 – 200 microns
C. 500 – 1000 microns
D. 10 – 50 Angstrom
Addition of a non-volatile solute to a solvent produces a _____ in its solvent:
A. Freezing point elevation
B. Boiling point depression
C. Vapor pressure lowering
D. All A., B. & C.
6 gms of magnesium (atomic weight = 24), reacts with excess of an acid, the amount of H2 produced will be ____ gm:
A. 0.5
B. 1
C. 3
D. 5
Boiling point of a solution as compared to that of the corresponding solvent is:
A. Less
B. More
C. Same
D. Either more or less
Number of gm moles of solute dissolved in 1 kg of solvent is called its:
A. Normality
B. Molarity
C. Molality
D. Formality
Assuming that CO2 obeys perfect gas law, calculate the density of CO2 (in kg/m3) at 263°C and 2 atm:
A. 1
B. 2
C. 3
D. 4
1 Pascal (unit of pressure) is equal to _____ N/m2:
A. 10
B. 1
C. 0.1
D. 1000
Heat of solution in a system in which both solute and solvent are liquids is termed as:
A. Heat of solvation
B. Heat of hydration
C. Standard integral heat of solution
D. Heat of mixing
N.T.P. corresponds to:
A. 1 atm absolute pressure & 0°C
B. 760 mm Hg gauge pressure & 0°C
C. 760 torr & 15°C
D. 101.325 KPa gauge pressure & 0°C
‘Giga’ stands for:
A. 109
B. 10-12
C. 1012
D. 1015
The pH value of a solution is 5.9. If the hydrogen ion concentration is decreased hundred times, the solution will be:
A. Basic
B. More acidic
C. Neutral
D. Of the same acidity
In case of an unsaturated vapor-gas mixture, the humid volume increases with increase in the:
A. Total pressure
B. Absolute humidity at a given temperature
C. Both A. and B.
D. Neither A. nor B.
1 gm mole of methane (CH4) contains:
A. 6.02 × 1023 atoms of hydrogen
B. 4 gm atoms of hydrogen
C. 3.01 × 1023 molecules of methane
D. 3 gms of carbon
If pH value of an acidic solution is decreased from 5 to 2, then the increase in its hydrogen ion concentration is ____ times:
A. 10
B. 100
C. 1000
D. 10000
The equilibria relations in a multi-component and multiphase system cannot be calculated with the help of the:
A. Phase rule
B. Experimental data
C. Empirical equations
D. Theoretical equations
Solutions which distil without change in composition are called:
A. Ideal
B. Saturated
C. Supersaturated
D. Azeotropic
Cp is expressed in S.I. unit as:
A. J/kg.°K
B. 0°K
C. W/m2.°C
D. W/m.°K
Increasing the temperature of an aqueous solution will cause decrease in its:
A. Molality
B. Mole fraction
C. Weight percent
D. Molarity
Gases diffuse faster compared to liquids because of the reason that the liquid molecules:
A. Are held together by stronger inter-molecular forces
B. Move faster
C. Have no definite shape
D. Are heavier
If the pressure of a gas is reduced to half & its absolute temperature is doubled, then the volume of the gas will:
A. Be reduced to 1/4th
B. Increase four times
C. Increase two times
D. None of these
A ‘limiting reactant’ is the one, which decides the ____ in the chemical reaction:
A. Equilibrium constant
B. Conversion
C. Rate constant
D. None of these
1 torr is equivalent to:
A. 1 mm Hg
B. 1 Pascal
C. 1 atm
D. 1 mm wc
An aqueous solution of 2.45% by weight H2SO4 has a specific gravity of 1.011. The composition expressed in normality is:
A. 0.2500
B. 0.2528
C. 0.5000
D. 0.5055
The temperature at which a real gas obeys Boyle’s law is termed as the:
A. Triple point
B. Boyle’s temperature
C. Eutectic point
D. Inversion temperature
Recycling in a chemical process facilitates:
A. Increased yield
B. Enrichment of product
C. Heat conservation
D. All A., B. & C.
Internal energy is independent of the ____ for an ideal gas:
A. Pressure
B. Volume
C. Both A. & B.
D. Neither A. nor B.
“The total volume occupied by a gaseous mixture is equal to the sum of the pure component volumes”. This is the _____ law:
A. Dalton’s
B. Amagat’s
C. Gay-Lussac’s
D. Avogadro’s
Which of the following gravity scales is used exclusively for liquids heavier than water:
A. Baume scale
B. Twaddell scale
C. API scale
D. None of these
1m3 is approximately equal to:
A. 28 litres
B. 35 ft3
C. 4.5 litres
D. 4.5 ft3
____ fuels require the maximum percentage of ‘excess air’ for complete combustion:
A. Solid
B. Liquid
C. Gaseous
D. Nuclear
Acidity or alkanity of a solution is expressed by its pH value, which is defined as (where, [H+] = hydrogen ion concentration in the solution):
A. log (1/H+)
B. – log (1/H+)
C. 1/log H+
D. None of these
Heat of transition is the heat evolved or absorbed, when a substance is converted from:
A. Vapor to liquid
B. Vapor to solid
C. Solid to liquid
D. One allotropic form to another allotropic form
The vapor pressure of water at 100°C is:
A. 100 N/m2
B. 76 cms of Hg
C. 13.6 cms of Hg
D. 760 mm wc
The OH- concentration in a solution having pH value 3 is:
A. 10-3
B. 10-10
C. 10-11
D. 10-13
pH value of H2SO4 (5% concentration) is:
A. 5
B. 7
C. > 7
D. < 7
Raoult’s law is not applicable to the:
A. Solutes which dissociate or associate in the particular solution
B. Concentrated solutions
C. Both B. & C.
D. Solutions containing non-volatile solute
Heat of neutralisation of HCl and NaOH is – 57.46 kJ/Kg mole. The heat of ionisation of water will be ____ kJ/Kg mole:
A. 57.46
B. -57.46
C. 114.92
D. -28.73
Which of the following is followed by an ideal solution:
A. Boyle’s law
B. Amagat’s law
C. Raoult’s law
D. Trouton’s rule
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
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
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
Mollier diagram is a plot of:
A. Temperature vs. enthalpy
B. Temperature vs. enthalpy
C. Entropy vs. enthalpy
D. Temperature vs. internal energy
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
In a turbine, the fluid expands almost:
A. Isothermally
B. Isobarically
C. Adiabatically
D. None of these
The number of degrees of freedom at the triple point of water is:
A. 0
B. 1
C. 2
D. 3
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
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
Enthalpy ‘H’ is defined as:
A. H = E – PV
B. H = F – TS
C. H – E = PV
D. None of these
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
When a gas in a vessel expands, its internal energy decreases. The process involved is:
A. Reversible
B. Irreversible
C. Isothermal
D. Adiabatic
For a single component two phase mixture, the number of independent variable properties are:
A. Two
B. One
C. Zero
D. Three
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
What is the value of ln y (where y = activity co-efficient) for ideal gases:
A. Zero
B. Unity
C. Infinity
D. Negative
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
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
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
Joule-Thomson co-efficient for a perfect gas is:
A. Zero
B. Positive
C. Negative
D. None of these
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
The temperature at which both liquid and gas phases are identical, is called the ____ point:
A. Critical
B. Triple
C. Freezing
D. Boiling
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
Entropy is a/an:
A. State function
B. Macroscopic property
C. Extensive property
D. None of these
Isentropic process means a constant ____ process:
A. Enthalpy
B. Pressure
C. Entropy
D. None of these
For an ideal solution, the value of activity co-efficient is:
A. 0
B. 1
C. 2
Throttling (Joule-Thomson effect) process is a constant ____ process:
A. Enthalpy
B. Entropy
C. Pressure
D. None of these
Number of degrees of freedom for a three phase system in equilibrium comprising of three non-reacting chemical species is:
A. 2
B. 0
C. 1
D.
Entropy change of mixing two liquid substances depends upon the:
A. Molar concentration
B. Quantity (i.e. number of moles)
C. Both A. and B
D. Neither A. nor B
Free energy change at equilibrium is:
A. Zero
B. Positive
C. Negative
D. Indeterminate
Extensive properties of a thermodynamic system depend upon the _____ of the system:
A. Specific volume
B. Temperature
C. Mass
D. Pressure
In the reaction, represented by, 2SO2 + O2 ⇌ 2SO3; ΔH = – 42 kcal; the forward reaction will be favoured by:
A. Low temperature
B. High pressure
C. Both A. and B
D. Neither A. nor B
Chemical potential is a/an:
A. Extensive property
B. Intensive property
C. Force which drives the chemical system to equilibrium
D. Both B. and C
______ functions are exemplified by heat and work:
A. Path
B. Point
C. State
D. None of these
Domestic refrigerator usually works on the _____ refrigeration cycle:
A. Carnot
B. Air
C. Absorption
D. vapour-ejection
In an isothermal process on an ideal gas, the pressure increases by 0.5 percent. The volume decreases by about _____ percent:
A. 0.25
B. 0.5
C. 0.75
D. 1
COP of a refrigerator drawing 1 kW of power per ton of refrigeration is about:
A. 0.5
B. 3.5
C. 4.5
D. 8.5
The unity of Planck’s constant ‘h’ in the equation, E = hv is:
A. J/s
B. J.S
C. J/kmol
D. kmol/J
The value of gas constant ‘R’ is:
A. 1.987 cal/gm mole °K
B. 1.987 BTU/lb. mole °R
C. Both A. and B
D. Neither A. nor B
Which is not a refrigerant:
A. SO2
B. NH3
C. CCl2F2
D. C2H4Cl2
Maxwell’s relation corresponding to the identity, dH = dS = Vdp + Σμi dni is:
A. (∂T/∂V)S, ni = -(∂P/∂S)V, ni
B. (∂S/∂P)T, ni = (∂V/∂T)P, ni
C. (∂S/∂V)T, ni = (∂P/∂T)V, ni
D. (∂T/∂P)S, ni = (∂V/∂S)P, ni
A system is said to be isopiestic, if there is no ______ change:
A. Temperature
B. Pressure
C. Volume
D. None of these
What is the number of degrees of freedom for liquid water in equilibrium with a mixture of nitrogen and water vapor:
A. 2
B. 0
C. 3
D. 1
Which of the following is not an equation of state:
A. Bertholet equation
B. Clausius-Clapeyron equation
C. Beattie-Bridgeman equation
D. None of these
The melting point of paraffin wax (which contracts on solidification) ____ with pressure rise:
A. Increases
B. Decreases
C. Remains unchanged
D. Decreases linearly
In a P-V diagram (for an ideal gas), an isothermal curve will coincide within adiabatic curve (through a point), when:
A. Cp < Cv
B. Cp = Cv
C. Cp > Cv
D. C ≥ Cv
The internal energy of an ideal gas does not change in a reversible _____ process:
A. Isothermal
B. Adiabatic
C. Isobaric
D. Isometric
Which of the following decreases with increase in pressure:
A. Melting point of ice
B. Melting point of wax
C. Boiling point of liquids
D. None of these
Near their critical temperatures, all gases occupy volumes ______ that of the ideal gas:
A. Less than
B. Same as
C. More than
D. Half
The number of degrees of freedom for a mixture of ice and water (liquid) are:
A. 3
B. 2
C. 1
D. 0
Boiling of liquid is accompanied with increase in the:
A. Vapor pressure
B. Specific Gibbs free energy
C. Specific entropy
D. All (A), B. and (C)
Refrigeration capacity of a household refrigerator may be round about ___ tons:
A. 0.15
B. 1.5
C. 4.5
D. 6.5
Which is not constant for an ideal gas:
A. (∂P/∂V)T
B. (∂V/∂T)P
C. (∂P/∂V)V
D. All (A), B. & (C)
Any substance above its critical temperature exists as:
A. Saturated vapour
B. Solid
C. Gas
D. Liquid
The difference between isothermal compressibility and adiabatic compressibility for an ideal gas is:
A. 0
B. +ve
C. -ve
D. ∞
In polytropic process (PVn = constant), if n = 1; it means a/an ____ process:
A. Adiabatic
B. Reversible
C. Isothermal
D. None of these
Which of the following equations is obtained on combining 1st and 2nd law of thermodynamics, for a system of constant mass:
A. dE = Tds – PdV
B. dQ = CvdT + PdV
C. dQ = CpdT + Vdp
D. Tds = dE – PdV
The internal energy of a gas obeying P (V – b) RT (where, b is a positive constant and has a constant Cv), depends upon its:
A. Pressure
B. Volume
C. Temperature
D. All A, B. & C
If the pressure on 100 c.c. of air is halved, then its volume (at the same temperature) would be _____ c.c:
A. 100
B. 50
C. 205
D. 200
All gases above its inversion temperature, in a throttling process will show:
A. A heating effect
B. No change in temperature
C. A cooling effect
D. Either A. or (C)
With increase in temperature, the internal energy of a substance:
A. Increases
B. Decreases
C. Remains unchanged
D. May increase or decrease; depends on the substance
(∂H/∂T)P is the mathematical expression for:
A. CV
B. Entropy change
C. Gibbs free energy
D. None of these
The entropy change in a reversible isothermal process, when an ideal gas expands to four times its initial volume is:
A. R loge 4
B. R log10 4
C. Cv log10 4
D. Cv loge 4
The unit of equilibrium constant of a chemical reaction is the same as that of:
A. Molar concentration
B. Temperature
C. Internal energy
D. None of these
A liquid under pressure greater than its vapour pressure for the temperature involved is called a ____ liquid:
A. Sub-cooled
B. Saturated
C. Non-solidifiable
D. None of these
The first law of thermodynamics is a restatement of the law of conservation of:
A. Mass
B. Energy
C. Momentum
D. None of these
____ decreases during adiabatic throttling of a perfect gas:
A. Entropy
B. Temperature
C. Enthalpy
D. Pressure
Change of state namely evaporation condensation, freezing and melting is an ____process:
A. Isothermal
B. Adiabatic
C. Isobaric
D. Isochoric
Claude gas liquefaction process employs cooling:
A. At constant pressure
B. By throttling
C. By expansion in an engine
D. None of these
The activity of an ideal gas is numerically _____ its pressure:
A. More than
B. Less than
C. Equal to
D. Data insufficient, can’t be predicted
During the phase transition, _____ changes:
A. Pressure
B. Volume
C. Temperature
D. All A , B. and C
Clausius-Clapeyron equation is applicable to ____ equilibrium processes:
A. Solid-vapor
B. Solid-liquid
C. Liquid-vapor
D. All A, B. and C
The four properties of a system viz. P, V, T, S are related by ____ equation:
A. Gibbs-Duhem
B. Gibbs-Helmholtz
C. Maxwell’s
D. None of these
Translational kinetic energy of molecules of an ideal gas is proportional to (where, T = absolute temperature of the gas):
A. T
B. √T
C. T2
D. 1/√T
One ton of refrigeration is defined as the heat rate corresponding to melting of one ton of ice in one:
A. Hour
B. Day
C. Minute
D. Second
4 kg moles of an ideal gas expands in vacuum spontaneously. The work done is:
A. 4 J
B. ∞
C. 0
D. 8 J
Specific/molar Gibbs free energy for a pure substance does not change during:
A. Sublimation
B. Vaporisation
C. Melting
D. Either A, B. or C.
The expression, nCv(T2 – T1), is for the _____ of an ideal gas:
A. Work done under adiabatic condition
B. Co-efficient of thermal expansion
C. Compressibility
D. None of these
Partial molar free energy of an element A in solution is same as its:
A. Chemical potential
B. Activity
C. Fugacity
D. Activity co-efficient
Entropy of the system decreases, when:
A. Snow melts into water
B. A gas expands spontaneously from high pressure to low pressure
C. Water is converted into ice
D. Both B. & C
The Maxwell relation derived from the differential expression for the Helmholtz free energy (dA) is:
A. (∂T/∂V)S = – (∂P/∂S)V
B. (∂S/∂P)T = – (∂V/∂T)P
C. (∂V/∂S)P = (∂T/∂P)S
D. (∂S/∂V)T = (∂P/∂T)V
Specific heat of a gas for a reversible adiabatic process is:
A. Negative
B. Zero
C. Infinity
D. None of these
Heat requirement for decomposition of a compound into its elements is _____ that is evolved during the formation of that compound from its elements:
A. The same
B. Less than
C. Greater than
D. Different than
For an ideal gas, the chemical potential is given by:
A. RT d ln P
B. R d ln P
C. R d ln f
D. None of these
The thermodynamic law, PVy = constant, is not applicable in case of:
A. Ideal compression of air
B. Free expansion of an ideal gas
C. Adiabatic expansion of steam in a turbine
D. Adiabatic compression of a perfect gas
If the molar heat capacities (Cp or Cv) of the reactants and products of a chemical reaction are identical, then, with the increase in temperature, the heat of reaction will:
A. Increase
B. Decrease
C. Remain unaltered
D. Increase or decrease; depends on the particular reaction
After throttling, gas temperature:
A. Decreases
B. Increases
C. Remain same
D. May increase or decrease; depends on the nature of the gas
Co-efficient of performance for a reversed Carnot cycle working between temperatures T1 and T2 (T1 > T2) is:
A. T2/(T1 – T2)
B. T1/(T1 – T2)
C. (T1 – T2)/T1
D. (T1 – T2)/T2
Work done is a:
A. Property of the system
B. Path function
C. Point function
D. State description of a system
For a constant pressure reversible process, the enthalpy change (ΔH) of the system is:
A. Cv.dT
B. Cp.dT
C. ∫ Cp.dT
D. ∫ Cv.dT
When pressure is applied on the system, ice ↔ water, then:
A. Equilibrium cannot be established
B. More ice will be formed
C. More water will be formed
D. Evaporation of water will take place
In an irreversible process:
A. Tds = dE – dW = 0
B. dE – dW – Tds = 0
C. Tds – dE + dW < 0
D. Tds – dT + dW < 0
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:
A. 12 P1V1
B. 6 P1 V1
C. 3 P1V1
D. P1 V1
The work done in an adiabatic change in a particular gas depends upon changes in the ____ only:
A. Temperature
B. Specific heat
C. Volume
D. Pressure
Entropy change for an irreversible isolated system is:
A. ∞
B. 0
C. < 0
D. > 0
_____ law of thermodynamics ascertains the direction of a particular spontaneous process:
A. Zeroth
B. First
C. Second
D. Third
On opening the door of an operating refrigerator kept in a closed room, the temperature of the room will:
A. Increase
B. Decrease
C. Remain same
D. Increase in summer and will decrease in winter
The principle applied in liquefaction of gases is:
A. Adiabatic expansion
B. Joule-Thomson effect
C. Both A. and B
D. Neither A. nor B
Entropy change of the reaction, H2O (liquid) → H2O (gas), is termed as the enthalpy of:
A. Solution
B. Vaporisation
C. Formation
D. Sublimation
What happens in a reversible adiabatic expansion process:
A. Heating takes place
B. Cooling takes place
C. Pressure is constant
D. Temperature is constant
Number of phases in a colloidal system is:
A. 1
B. 2
C. 3
D. 4
Isotherm on an enthalpy-concentration diagram, for an ideal solution will be a:
A. Straight line
B. Sine curve
C. Parabola
D. Hyperbola
In a reversible process:
A. Tds = dE + dW
B. dE – dW = Tds
C. dW – dE = Tds
D. Tds – dW + dE >0
A system in which there is exchange of energy but not of mass, is called a/an _____ system:
A. Isolated
B. Open
C. Insulated
D. Closed
The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be:
A. More
B. Less
C. Same
D. Data insufficient to predict
With increase in pressure (above atmospheric pressure), the Cp of a gas:
A. Increases
B. Decreases
C. Remains unchanged
D. First decreases and then increases
PVy = constant, holds good for an isentropic process, which is:
A. Reversible and isothermal
B. Isothermal and irreversible
C. Reversible and adiabatic
D. Adiabatic and irreversible
As the temperature is lowered towards the absolute zero, the value of ∂(ΔF)/∂T, then approaches:
A. Unity
B. Zero
C. That of the heat of reaction
D. Infinity
Which of the following is a thermodynamic property of a system:
A. Concentration
B. Mass
C. Temperature
D. Entropy
The amount of heat required to decompose a compound into its elements is ____ the heat of formation of that compound from its elements:
A. Less than
B. More than
C. Same as
D. Not related to
Gases are cooled in Joule-Thomson expansion, when it is _____ inversion temperature:
A. Below
B. At
C. Above
D. Either B. or C.
Number of components (C), phase (P) and degrees of freedom (F) are related by Gibbs phase rule as:
A. P + F – C = 2
B. C = P – F + 2
C. F = C – P – 2
D. P = F – C – 2
Entropy change in case of reversible adiabatic process is:
A. Minimum
B. Zero
C. Maximum
D. Indeterminate
Fundamental principle of refrigeration is based on the _____ law of thermodynamics:
A. Zeroth
B. First
C. Second
D. Third
For a constant volume process:
A. dE = CpdT
B. dE = CvdT
C. dQ = dE + pdV
D. dW = pdV
At absolute zero temperature, the _____ of the gas is zero:
A. Pressure
B. Volume
C. Mass
D. None of these
Joule-Thomson Co-efficient at any point on the inversion curve is:
A. ∞
B. +ve
C. 0
D. -ve
No work is done by the system, when a reaction occurs at constant:
A. Volume
B. Temperature
C. Pressure
D. None of these
If atmospheric temperature and dew point are nearly equal, then the relative humidity is:
A. Zero
B. 50%
C. Almost 100%
D. unpredictable
What is the value of Joule-Thomson co-efficient for an ideal gas:
A. +ve
B. -ve
C. 0
D. ∞
In any spontaneous process, the ______ free energy decreases:
A. Helmholtz
B. Gibbs
C. Both A. & B.
D. Neither A. nor B.
Molar heat capacity of water in equilibrium with ice at constant pressure is ____ Kcal/kg mole. °K:
A. 0
B. ∞
C. 50
D. 100
The compressibility factor of a gas is given by (where, V1 = actual volume of the gas V2 = gas volume predicted by ideal gas law):
A. V1/V2
B. V2/V1
C. V1 – V2
D. V1.V2
The freezing point of a liquid decreases when the pressure is increased, if the liquid ____ while freezing:
A. Contracts
B. Expands
C. Does not change in volume
D. Either (A), B. or (C)
The number of degrees of freedom for an azeotropic mixture in a two component vapour liquid equilibria is/are:
A. Zero
B. One
C. Two
D. Three
For any system, what is the minimum number of degrees of freedom:
A. 0
B. 1
C. 2
D. 3
What is the degree of freedom for two miscible (non-reacting) substances in vapor-liquid equilibrium forming an azeotrope:
A. 0
B. 1
C. 2
D. 3
Which of the following liquid metals has the highest thermal conductivity:
A. Molten sodium
B. Molten lead
C. Mercury
D. Molten potassium
High ____ is an undesirable property for a good refrigerant:
A. Specific heat
B. Latent heat of vaporisation
C. Viscosity
D. Specific vapor volume
Specific ____ does not change during phase change at constant temperature and pressure:
A. Entropy
B. Gibbs energy
C. Internal energy
D. Enthalpy
A change in state involving a decrease in entropy can be spontaneous, only if:
A. It is exothermic
B. It is isenthalpic
C. It takes place isothermally
D. It takes place at constant volume
For a constant volume process ____ by the system is used only to increase the internal energy:
A. Heat absorbed
B. Work done
C. Both A. & B
D. Neither A. nor B
Internal energy of an element at 1 atm and 25° C is _____ kcal/kg.mole:
A. 0
B. 273
C. 25
D. None of these
Which of the following processes cannot be made reversible even under ideal condition of operation:
A. Free expansion of a gas
B. Compression of air in a compressor
C. Expansion of steam in a turbine
D. All (A), B. & (C)
Joule-Thomson co-efficient depends on the:
A. Pressure
B. Temperature
C. Both A. & B
D. Neither A. nor B
The enthalpy change when ammonia gas is dissolved in water is called the heat of:
A. Solution
B. Formation
C. Dilution
D. Combustion
______ increases with increase in pressure:
A. The melting point of wax
B. The boiling point of a liquid
C. Both A. and B
D. Neither A. nor B
For organic compounds, group contribution method can be used for the estimation of:
A. Critical properties
B. Specific gravity
C. Specific volume
D. Thermal conductivity
The value of Cp and Cv respectively for monatomic gases in Kcal/kg Mole.°K are:
A. 5 & 3
B. 3.987 & 1.987
C. 1.987 & 0.66
D. 0.66 & 1.987
The temperature at the eutectic point of the system is the ____ temperature that can be attained in the system:
A. Lowest
B. Highest
C. Average
D. None of these
For an ideal gas, the internal energy depends upon its _____ only:
A. Molecular size
B. Temperature
C. Volume
D. Pressure
Pick out the undesirable property for a good refrigerant:
A. High thermal conductivity
B. Low freezing point
C. Large latent heat of vaporisation
D. High viscosity
Filling of gas from a high pressure cylinder into small bottles is an example of a/an _____ process:
A. Equilibrium
B. Adiabatic
C. Steady
D. Unsteady
Degree of freedom of the system ice-water-vapour will be:
A. 0
B. 1
C. 2
D. 3
If we increase the pressure on a substance (which is at its triple point), then the triple point:
A. Increases
B. Decreases
C. Remains unchanged
D. May increase or decrease; depends on the substance
Heating of water under atmospheric pressure is an _____ process:
A. Isochoric
B. Isobaric
C. Adiabatic
D. Isothermal
In a homogeneous solution, the activity co-efficient of a component depends upon the:
A. Pressure
B. Composition
C. Temperature
D. All (A), B. and (C)
For an ideal liquid solution, which of the following is unity:
A. Activity
B. Fugacity
C. Activity co-efficient
D. Fugacity co-efficient
Internal energy is equal to the heat absorbed in case of a/an _____ process:
A. Constant volume
B. Polytropic
C. Adiabatic
D. Constant pressure
The expression for entropy change, ΔS = n Cp . ln (T2/T1), is valid for the _____ of a substance:
A. Simultaneous pressure & temperature change
B. Heating
C. Cooling
D. Both B. and C
Minimum number of phases that exists in a system is 1. Number of chemical species in a colloidal system is:
A. 1
B. 2
C. 3
D. 4
For a real gas, the chemical potential is given by:
A. RT d ln P
B. RT d ln f
C. R d ln f
D. None of these
The free energy change for a chemical reaction is given by (where, K = equilibrium constant):
A. RT ln K
B. -RT ln K
C. -R ln K
D. T ln K
For the reversible exothermic reaction, N2 + 3H2 ⇌ 2NH3, increase of pressure would:
A. Shift the equilibrium towards right
B. Give higher yield of NH3
C. Both B. and C
D. Neither A. nor B
Heat is added at constant pressure in an ideal ____ cycle:
A. Stirling
B. Brayton
C. Rankine
D. Both B. and C
PVγ = Constant (where, γ = Cp/Cv) is valid for a/an ______ process:
A. Isothermal
B. Isentropic
C. Isobaric
D. Adiabatic
The expression for entropy change given by, ΔS = – nR ln (P2/P1), holds good for:
A. Expansion of a real gas
B. Reversible isothermal volume change
C. Heating of an ideal gas
D. Cooling of a real gas
dW and dq are not the exact differential, because q and W are:
A. State functions
B. Path functions
C. Intensive properties
D. Extensive properties
(∂E/∂T)V is the mathematical expression for:
A. CV
B. Enthalpy change
C. Free energy change
D. None of these
A/an ____ system is exemplified by a vessel containing a volatile liquid in contact with its vapor:
A. Isolated
B. Closed
C. Open
D. None of these
In case of steady flow compression polytropic process (PVn = constant), the work done on air is the lowest, when:
A. n = y = 1.4
B. n = 0
C. n = 1
D. n = 1.66
In which of the following reaction equilibrium, the value of equilibrium constant Kp will be more than is Kc:
A. 2HI ⇌ H2 + I2
B. N2O4 ⇌ 2NO2
C. 2SO2 + O2 ⇌ 2SO3
D. None of these
The partial pressure of each constituent present in an alloy is ___ the total vapor pressure exerted by the alloy:
A. Less than
B. Equal to
C. More than
D. Either B. or C; depends on the type of alloy
In any spontaneous process:
A. Only F decreases
B. Only A decreases
C. Both F and A decreases
D. Both F and A increase
The change in Gibbs free energy for vaporisation of a pure substance is:
A. Positive
B. Negative
C. Zero
D. May be positive or negative
Answer: Option B 392. Keeping the pressure constant, to double the volume of a given mass of an ideal gas at 27°C, the temperature should be raised to _____ °C:
A. 270
B. 327
C. 300
D. 540
Free energy:
A. Decreases in all spontaneous (or irreversible) processes
B. Change during a spontaneous process has a negative value
C. Remains unchanged in reversible processes carried at constant temperature and pressure
D. All A, B. and C
Degrees of freedom at triple point will be:
A. 0
B. 1
C. 2
D. 3
For an irreversible process involving only pressure-volume work:
A. (dF)T, p <0
B. (dF)T, p = 0
C. (dF)T, p > 0
D. (dA)T, v >0
Out of the following refrigeration cycles, which one has the minimum COP (Co-efficient of performance):
A. Air cycle
B. Carnot cycle
C. Ordinary vapour compression cycle
D. Vapour compression with a reversible expansion engine
With increase in temperature, the atomic heat capacities of all solid elements:
A. Increases
B. Decreases
C. Remains unchanged
D. Decreases linearly
Which of the following behaves most closely like an ideal gas:
A. He
B. N2
C. O2
D. H2
For a multi-component system, the term chemical potential is equivalent to the:
A. Molal concentration difference
B. Molar free energy
C. Partial molar free energy
D. Molar free energy change
Fugacity co-efficient of a substance is the ratio of its fugacity to:
A. Mole fraction
B. Activity
C. Pressure
D. Activity co-efficient
As the entropy of the universe is increasing, day by day, the work producing capacity of a heat engine is:
A. Not changed
B. Decreasing
C. Increasing
D. Data sufficient, can’t be predicted
The standard state of a gas (at a given temperature) is the state in which fugacity is equal to:
A. Unity
B. Activity
C. Both A. & B
D. Neither A. nor B
Joule-Thomson experiment is:
A. Isobaric
B. Adiabatic
C. Isenthalpic
D. Both B. & C.
Degree of freedom of a system consisting of a gaseous mixture of H2 and NH3 will be:
A. 0
B. 1
C. 2
D. 3
Gibbs free energy of a pure fluid approaches ____ as the pressure tends to zero at constant temperature:
A. Infinity
B. Minus infinity
C. Zero
D. None of these
Which is a state function:
A. Specific volume
B. Work
C. Pressure
D. Temperature
The quantitative effect of temperature on chemical equilibrium is given by the:
A. Van’t-Hoff equation
B. Le-Chatelier’s principle
C. Arrhenius equation
D. None of these
The ammonia synthesis reaction represented by N2 + 3H2 ⇌ 2NH3; ΔH = – 22.4 kcal, is:
A. Endothermic
B. Exothermic
C. Isothermal
D. Adiabatic
Gibbs free energy at constant pressure and temperature under equilibrium conditions is:
A. ∞
B. 0
C. Maximum
D. Minimum
Consider the reaction, C + O2 ⇌ CO2; ΔH = – 94 kcal. What will be the value of ΔH for the reaction CO2 → C + O2:
A. -94 kcal
B. +94 kcal
C. > 94 kcal
D. < -94 kcal
Entropy is a measure of the ____ of a system:
A. Disorder
B. Orderly behaviour
C. Temperature changes only
D. None of these
An isentropic process is carried out at constant:
A. Volume
B. Pressure
C. Temperature
D. All (A), B. and (C)
The specific heat of saturated water vapour at 100°C is:
A. ∞
B. -ve
C. 0
D. +ve
Specific volume of an ideal gas is:
A. Equal to its density
B. The reciprocal of its density
C. Proportional to pressure
D. None of these
The point at which all the three (solid, liquid and gas) phases co-exist, is known as the ____ point:
A. Freezing
B. Triple
C. Boiling
D. Boyle
Which of the following has the least thermal efficiency:
A. Steam engine
B. Carnot engine
C. Diesel engine
D. Otto engine
Heat evolved/absorbed during conversion of a substance from one allotropic form to another is termed as the heat of:
A. Fusion
B. Vaporisation
C. Transition
D. None of these
Heat is added at constant temperature in an ideal ______ cycle:
A. Stirling
B. Brayton
C. Rankine
D. None of these
A gas can be liquefied by pressure alone only, when its temperature is _____ its critical temperature:
A. Less than
B. More than
C. Equal to or higher than
D. Less than or equal to
“If different processes are used to bring about the same chemical reaction, the enthalpy change is same for all of them”. This is _____ law:
A. Hess’s
B. Kirchoff’s
C. Lavoisier and Laplace
D. None of these
Which of the following test is used for distinguishing among dry oils, semi-drying oils and non drying oils:
A. Elaiden test
B. Reichert-Meissl value test
C. Hunter value test
D. Iodine value test
Laser welding is widely employed in the _______ industries:
A. Electronic
B. Structural
C. Process
D. Heavy
Joining of thin foils is preferred to be done by:
A. Gamma rays
B. X-rays
C. Microwaves
D. Gas welding
About _____ ton of coke is required in a cupola to produce one ton of casting:
A. 0.03
B. 0.3
C. 0.8
D. 1.5
Satellites burn off during re-entry to earth’s atmosphere, because of the:
A. Combustion with air
B. Gravitational pull by earth
C. Friction with earth’s atmosphere
D. Loss in weight of the satellite
Filler material used in welding should have _____ as compared to the parent metal to be welded:
A. Lower melting temperature
B. Same melting temperature
C. Same composition
D. Both ‘B’ & ‘C’
The only suitable method for hardening the low carbon steel is case hardening. Which of the following is a case hardening process:
A. Cyaniding
B. Sherardizing
C. Spheroidising
D. None of these
With increase in temperature, the electrical conductivity of semiconductors:
A. Increases
B. Decreases
C. Remain constant
D. Either A. or B. depends on the type of semi-conductor
Silicon percentage in silicon steel used for electrical equipments is about:
A. 1
B. 4.0
C. 8
D. 14
Babbitt lining is used on brass/bronze bearings to increase the:
A. Antifriction properties
B. Compressive strength
C. Bearing resistance
D. Wear resistance
Window panes of aeroplanes are normally made of:
A. Perspex (PMMA)
B. Teflon (PTFE)
C. Bakelite (phenol formaldehyde)
D. Polystyrene
Which of the following hardness tests does not measure the indentation hardness of metals and alloys:
A. Vickers hardness test
B. Shore scleroscope test
C. Brinell hardness test
D. Rockwell hardness test
Which of the following approaches the ideal gas behaviour most closely:
A. Wet steam
B. Saturated steam
C. Superheated steam
D. Saturated water
Normalising does not _______ of a metal:
A. Improve machinability & tensile strength
B. Remove internal stresses
C. Refine the structure
D. Remove strains caused by cold working
Gratings is associated with the measurement of:
A. Linear displacement
B. Concavity/convexity
C. Surface texture
D. Flatness
Water flow in the river during flood can be categorized as the ______ flow:
A. Unsteady uniform
B. Unsteady non-uniform
C. Steady uniform
D. Steady non-uniform
The capacity of a spring to store energy is called the spring form co-efficient. Stiffness of a spring is measured by the:
A. Ability to absorb shock
B. Capacity to store energy
C. Ratio of the wire & coil diameters
D. Load to produce unit deflection
Out of the following, the best material capable of withstanding shock & vibration without the danger of cracking is:
A. Malleable iron
B. Grey cast iron
C. Chilled cast iron
D. White cast iron
The most serious manufacturing defect from fracture toughness point of view is:
A. Surface roughness
B. Pores
C. Spherical inclusion
D. Crack
______ has the highest melting point out of the following:
A. Tungsten
B. Zirconium
C. Molybdenum
D. Tantalum
Air-petrol ratio for maximum power generation in spark ignition engine is about:
A. 6 : 1
B. 12 : 1
C. 18 : 1
D. 24 : 1
Galvanic corrosion cannot be prevented by:
A. Cathodic protection
B. Anodic protection
C. Usage of largest possible anodic area
D. Any one of these
Fire in fuel gas pipelines is extinguished most effectively by:
A. Spraying water
B. Blanketting the area with nitrogen atmosphere
C. Fire fighting foam
D. None of these
Fibrous fracture is normally encountered in the ____ materials:
A. Hard
B. Elastic
C. Ductile
D. Brittle
The elastic strain energy of a unit length of an edge dislocation as compared to that of a screw dislocation is:
A. More
B. Equal
C. Less
D. Double
Addition of silicon to cast iron:
A. Promotes graphite module formation
B. Improves its ductility
C. Does not promote graphite flakes formation
D. Increases the fluidity of molten metal
______ is used as a material of construction for the blade of power saw:
A. Wrought iron
B. Stainless steel
C. Mild steel
D. High speed steel
Shaft/rotor speed is most accurately measured by a:
A. Frequency counter
B. Tachometer
C. Strobometer
D. Speedometer
Factor of safety is the ratio of the ______ stress to the working stress:
A. Tensile
B. Compressive
C. Yield
D. Bearing
The escape velocity of a body on earth which is independent of its mass is about ______ km/second:
A. 3
B. 7
C. 11
D. 15
Magnetic permeability of iron is increased by its:
A. Decarburising
B. Alloying with cobalt
C. Purification
D. Alternate heating & cooling
The main reducing agent in iron blast furnace is:
A. Carbon dioxide
B. Carbon monoxide
C. Oxygen
D. Air
Broaching tools are usually made of:
A. Cermets
B. High speed steel
C. Tungsten carbide
D. Stellite
Temper brittleness of a material can be fairly detected by the _____ test:
A. Fatigue
B. Notched bar impact
C. Tensile
D. Hardness
There are one octahedral void and _____ tetrahedral void in the closest packing of atoms:
A. One
B. Two
C. Three
D. None of these
Addition of small amount of _____ to grey cast iron is done to produce nodular grey cast iron:
A. Manganese
B. Phosphorous
C. Magnesium
D. Chromium
_____ remains constant during the adiabatic cooling of moist air:
A. Wet bulb temperature
B. Dry bulb temperature
C. Relative humidity
D. Specific humidity
Yield strength of a material is determined by the ______ test:
A. Creep
B. Tension
C. Compression
D. Endurance
In an eutectic system, two elements are completely:
A. Soluble in solid state
B. Insoluble in liquid state
C. Insoluble in both solid & liquid state
D. Soluble in liquid state
A solution which resists change in its pH value on addition of acid/alkali is called the ____ solution:
A. Neutral
B. Ideal
C. Buffer
D. Zero pH
The material used for coating the welding electrode is termed as the:
A. Flux
B. Slag
C. Protective layer
D. Binder
In chemical dehumidification process:
A. Wet bulb temperature increases
B. Dry bulb temperature remains constant
C. Dew point temperature increases
D. Dry bulb temperature increases
Which of the following is an example of stress corrosion:
A. Season cracking of brass
B. Caustic embrittlement of steel
C. Both A. & B.
D. Neither A. nor (B)
_____ joint is mostly used for joining pipes carrying water at low pressure:
A. Nipple
B. Socket
C. Union
D. Bell and spigot
Silicon percentage in the silicon steel used for electrical appliances/equipments is:
A. 0.3-0.4
B. 12-14
C. 3-4
D. 20-25
Annealing of cast iron:
A. Softens it to facilitate machining
B. Decreases the free carbon
C. Increases the strength
D. None of these
Thermistors are used in _____ devices:
A. Voltage measuring
B. Temperature measuring
C. Temperature compensating
D. Both B. & C.
The dew point of moist air becomes ______ with decrease in its relative humidity:
A. Less than the wet bulb temperature
B. More than the wet bulb temperature
C. More than the dry bulb temperature
D. Equal to wet bulb temperature
Basicity [%Cao + %MgO + %SiO2) of the slag in Indian blast furnace is in the range of:
A. 0.7-1.0
B. 1.1-1.4
C. 1.5 – 1.8
D. 2.0 – 2.5
The most commonly used moderator in nuclear power plants is:
A. Graphite
B. Light water
C. Heavy water
D. Beryllium
Eutectic reaction for iron-carbon system occurs at a temperature of _____ °C:
A. 723
B. 959
C. 1147
D. 1493
Minimum thermal efficiency of a steam boiler may be around _______ percent:
A. 25
B. 45
C. 65
D. 20
Corona discharge is related to the operation of a/an:
A. Induction motor
B. Electrostatic precipitator
C. Fast breeder reactor
D. Magneto hydrodynamic generator (MHD)
Silicon crystal can be converted to p-type semi-conductor by doping with:
A. Phosphorous
B. Nitrogen
C. Carbon
D. Boron
Which of the following is normally not found in both the S.I. (petrol) & C.I. (diesel) engines:
A. Air filter
B. Fuel injector
C. Exhaust silencer
D. Battery
Vibration upto 100 kilo hertz can be most accurately measured by a ____ type accelerometer:
A. Preloaded spring
B. Piezoelectric
C. Bonded strain gauge
D. None of these
Brinell Hardness Number (BHN) for talc is approximately in the range of:
A. 1-5
B. 20-30
C. 100-150
D. 200-250
Pressure exerted by a liquid depends upon its:
A. Surface tension
B. Density
C. Viscosity
D. Buoyancy
Drills are usually made of:
A. Cermets
B. High speed steel
C. Alloy steel
D. Tungsten carbide
An ideal material for making cooking vessels should have:
A. High heat capacity
B. Low heat capacity
C. High thermal conductivity
D. Both B. and C.
Propulsion of rocket follows from the:
A. Newton’s second law of motion
B. Newton’s third law of motion
C. Law of projectiles
D. Archimedes principle
Which of the following is an example of cathodic protection of metals against corrosion:
A. Painted steel
B. Galvanised iron
C. Case hardened steel
D. Lead lined reactor
The _____ of a double acting reciprocating pump as compared to the single acting pump will be almost double:
A. Flow output
B. Head developed
C. Overall efficiency
D. Weight
Out of the following, the alloy which has equal percentage of constituents, is:
A. White metal
B. Gun metal
C. Duralumin
D. Constantan
The bolt is subjected to ____ when the nut is tightened by putting the washer beneath it:
A. Tension
B. Shear
C. Compression
D. Bending & tension
The joint for soldering is supported by binding wire made of:
A. Mild steel
B. Copper
C. Soft iron
D. Stainless steel
Tesla metre per ampere (T. m/A) is the unit for the measurement of:
A. Magnetic susceptibility
B. Magnetic moment
C. Permeability of free space
D. Flux density
The units of the rate constant for a second order reaction are:
A. Sec-1. mole°
B. Moles1. sec-1
C. Moles-1. sec1
D. Moles1. sec1
Between 230 and 370°C, blue brittleness is caused in mild steel because of the:
A. Immobility of dislocation
B. Strain-ageing
C. Increase in Young’s modulus
D. Strain hardening
Principal alloying element in Elinvar (used for making hair springs for watches) is:
A. Copper
B. Aluminium
C. Nickel
D. Zinc
Neutrons are present in all atoms except that of:
A. He
B. C
C. H
D. Ar
An atom bomb works on the principle of:
A. Nuclear fission
B. Nuclear fusion
C. Both the nuclear fission & fusion
D. Ionisation
A psychrometer does not measure the _____ temperature of moist air:
A. Dew point
B. Dry bulb
C. Wet bulb
D. None of these
With increase in _____ Knocking tendency in a spark ignition petrol engine decreases:
A. Supercharging
B. Wall temperature
C. Compression ratio
D. Engine speed
Read More: Chemistry MCQs for all classes, admissions test and competitive exams preparation.