

MCQOPTIONS
Saved Bookmarks
This section includes 2253 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
851. |
Out of the following substances, one ton of __________ will store the maximum heat for a rise of 30°C in temperature. |
A. | Steel |
B. | Lignite |
C. | Water |
D. | Lime stone |
Answer» D. Lime stone | |
852. |
A hot short metal is |
A. | Hard when hot |
B. | Brittle when cold |
C. | Brittle when hot |
D. | Brittle under all conditions |
Answer» D. Brittle under all conditions | |
853. |
Heat flow across a hollow sphere of inner radius 'r₁' and outer radius 'r₂' is directly proportional to |
A. | (r₂ - r₁)/(r₁ - r₂) |
B. | (r₂ . r₁)/(r₂ - r₁) |
C. | (r₁ + r₂)/(r₁ . r₂) |
D. | (r₁ . r₂)/(r₁ + r₂) |
Answer» C. (r₁ + r₂)/(r₁ . r₂) | |
854. |
What is the critical radius of insulation (cms) for a metallic cylinder, if the convective heat transfer co-efficient with the ambient atmosphere is 5 W/m². °K ? Thermal conductivity of metal and insulation material are 40 and 0.1 W/m.°K respectively. |
A. | 2 |
B. | 5 |
C. | 10 |
D. | 20 |
Answer» B. 5 | |
855. |
While the recrystallisation temperature for pure metals is 0.3 Tm, the same for alloys is equal to __________ x Tm (where, Tm Melting temperature). |
A. | 0.25 |
B. | 0.45 |
C. | 0.70 |
D. | 0.95 |
Answer» D. 0.95 | |
856. |
The heat released by cooling one mole of copper from 400 K to room temperature (300 K) is (assume : Cp of copper is 23 J K⁻¹mole⁻¹) |
A. | 2300 J |
B. | 4600 J |
C. | 230 J |
D. | 2.3 x 106 J |
Answer» B. 4600 J | |
857. |
The cooling rate required to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours is __________ BTU/hr. |
A. | 100 |
B. | 200 |
C. | 1000 |
D. | 2000 |
Answer» C. 1000 | |
858. |
On being hit with a hammer, __________ will readily fracture. |
A. | Brass |
B. | Mild steel |
C. | Cast iron |
D. | Lead |
Answer» D. Lead | |
859. |
Scaling occurs in boiler tubes due to the fact that, the solubility of Ca(OH)₂ __________ with increasing temperature. |
A. | Increases |
B. | Decreases |
C. | Shows inversion of solubility |
D. | None of these |
Answer» B. Decreases | |
860. |
Two solutions A₁ & A₂ have pH value of 2 & 6 respectively. It implies that the solution |
A. | A₁ is more alkaline than solution A₂ |
B. | A₁ is highly acidic |
C. | A₂ is very slightly acidic |
D. | Both B & C |
Answer» E. | |
861. |
Austempering of steel requires.it to be heated to 875°C followed by sudden cooling to 250-525°C, thereby changing austenite to |
A. | Sorbite |
B. | Bainite |
C. | Martensite |
D. | Troostite |
Answer» C. Martensite | |
862. |
Super conduction in metals is observed at a temperature of __________ °K. |
A. | <100 |
B. | >100 |
C. | About 273 |
D. | About 373 |
Answer» C. About 273 | |
863. |
High speed steel tools retain their hardness upto a temperature of __________ °C. |
A. | 500 |
B. | 750 |
C. | 900 |
D. | 1100 |
Answer» D. 1100 | |
864. |
Eutectic reaction for iron-carbon system occurs at a temperature of __________ °C. |
A. | 723 |
B. | 959 |
C. | 1147 |
D. | 1493 |
Answer» B. 959 | |
865. |
Eutectoid reaction for iron-carbon system occurs at a temperature of __________ °C. |
A. | 597 |
B. | 959 |
C. | 1147 |
D. | 1493 |
Answer» E. | |
866. |
The ratio of thermal & electrical conductivity is same for all the metals at the same temperature ; and at around room temperature, this ratio is proportional to(where, T = absolute temperature, °K) |
A. | T |
B. | 1/T |
C. | T² |
D. | 1/T² |
Answer» B. 1/T | |
867. |
Electrolytic reduction cell used for conversion of calcined Al2O₃ to Al is a carbon lined furnace operating at 800-900 °C. The purpose of electric current supplied to the furnace is to |
A. | Achieve very high purity of aluminium (99.9%) |
B. | Keep the electrolyte in liquid condition by the generation of heat |
C. | Electrolytically dissociate alumina |
D. | Both(b) & (c) |
Answer» E. | |
868. |
In a totally irreversible isothermal expansion process for an ideal gas, ΔE = 0, ΔH = 0. Then ΔQ and ΔS will be |
A. | ΔQ = 0, ΔS=0 |
B. | ΔQ = 0 , ΔS = +ve |
C. | ΔQ = 0, ΔS = -ve |
D. | ΔQ = +ve , ΔS= +ve |
Answer» C. ΔQ = 0, ΔS = -ve | |
869. |
α-rays are |
A. | Negatively charged |
B. | Positively charged |
C. | Neutral |
D. | Same as X-rays |
Answer» C. Neutral | |
870. |
Pick out the wrong statement: |
A. | Soft water is more corrosive than that carrying calcium salts |
B. | The corrosion of brass condenser tubes handling brine solution is also termed as 'dezincification' |
C. | Non-annealed brass is highly susceptible to season cracking (i.e., inter-crystal corrosion due to internal stresses) |
D. | Pure copper is highly susceptible to stress corrosion |
Answer» E. | |
871. |
Which of the following is a synthetic abrasive ? |
A. | Corundum |
B. | Emery |
C. | Pumice |
D. | Silicon carbide |
Answer» E. | |
872. |
For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm³) while the C.V. is same on weight basis (i.e., kcal/kg) ? |
A. | Propane and acetylene |
B. | Propane and LPG |
C. | Sewage gas and gobar gas |
D. | B.F gas and coke oven gas |
Answer» E. | |
873. |
"Internal energy of a gas obeying Vanderwall's equation of state, (p + a/v²)(V - b) = RT , depends upon its" |
A. | Pressure & temperature |
B. | Pressure & specific volume |
C. | Temperature & specific volume |
D. | Temperature only |
Answer» B. Pressure & specific volume | |
874. |
Which of the following does not discharge the dust collected as a dry solid? |
A. | Electrostatic precipitator |
B. | Wet scrubber |
C. | Bag filter |
D. | Gravity settling chamber |
Answer» C. Bag filter | |
875. |
The following thermocouple may be used for measuring temperature upto 1873°K. |
A. | Chromel-alumel |
B. | Copper-constantan |
C. | Platinum-platinum rhodium |
D. | Iron-constatan |
Answer» D. Iron-constatan | |
876. |
In a forced draft cooling tower, water is cooled from 95 to 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the |
A. | Range is 15°F |
B. | Approach is 10°F |
C. | Both A & B |
D. | Neither A nor B |
Answer» D. Neither A nor B | |
877. |
In fluid flow, and heat and mass transfer, one encounters (i) kinematic velocity (μ), (ii) molecular diffusivity (θ) and thermal diffusivity (α). The units of these quantities are. |
A. | μ , α and θ all have units of m/s |
B. | μ , α and θ all have units of m²/s |
C. | α and θ have units of m²/s, while μ has unit of m/s |
D. | α and θ have units of m/s, while μ has unit of m²/s |
Answer» D. α and θ have units of m/s, while μ has unit of m²/s | |
878. |
FeO (s) + CO (g) = Fe (s) + CO₂ (g), k = 0. 435 at 1173E; At equilibrium, what will be the number of moles of CO gas required to reduce one mole of FeO at 1173 K? |
A. | 1.0 |
B. | 1.3 |
C. | 2.3 |
D. | 3.3 |
Answer» E. | |
879. |
Magnetic permeability of iron is increased by its |
A. | Decarburising |
B. | Alloying with cobalt |
C. | Purification |
D. | Alternate heating & cooling |
Answer» C. Purification | |
880. |
The unit of gc is |
A. | lbm/lbf . ft/seC₂ |
B. | lbf/lbm . ft/seC₂ |
C. | lbm/lbf . seC₂/ft |
D. | lbf/lbm . seC₂/ft |
Answer» B. lbf/lbm . ft/seC₂ | |
881. |
Which of the following is a weak acid? |
A. | HF |
B. | HCl |
C. | HI |
D. | HBr |
Answer» B. HCl | |
882. |
Which of the following heat treatment processes is used for softening the hardened material? |
A. | Normalising |
B. | Tempering |
C. | Annealing |
D. | None of these |
Answer» C. Annealing | |
883. |
Which of the following metals can not be hot worked at room temperature? |
A. | Zinc |
B. | Nickel |
C. | Lead |
D. | Tin |
Answer» C. Lead | |
884. |
__________ is not a case hardening process. |
A. | Carburising |
B. | Nitriding |
C. | Cyaniding |
D. | Annealing |
Answer» B. Nitriding | |
885. |
Which of the following is not used as a bearing material? |
A. | Copper-lead alloys |
B. | Babbits |
C. | Bronzes |
D. | Cermets |
Answer» E. | |
886. |
Which one can be directly solidified from gaseous state wihtout entering into liquid state? |
A. | Helium |
B. | Oxygen |
C. | Carbon dioxide |
D. | None of these |
Answer» D. None of these | |
887. |
Which of the following is not a suitable solid lubricant? |
A. | Talc |
B. | Molybdenum disulphide |
C. | Graphite |
D. | None of these |
Answer» E. | |
888. |
__________ glass is used in the mercury in glass thermometer meant for measuring a temperature of 500°C. |
A. | Borosilicate |
B. | High silica |
C. | Supermax |
D. | Lead |
Answer» D. Lead | |
889. |
Which of the following has the highest value of refractive index? |
A. | Brine (sea water) |
B. | Diamond |
C. | Distilled water |
D. | Glass |
Answer» C. Distilled water | |
890. |
Which of the following equipments is used for liquid dispersion? |
A. | Packed column |
B. | Venturi scrubber |
C. | Bubble cap plate column |
D. | Wetted wall column |
Answer» C. Bubble cap plate column | |
891. |
Which of the following forces does not act on a fluid at rest? |
A. | Viscous force |
B. | Gravity force |
C. | Hydrostatic force |
D. | Surface tension force |
Answer» B. Gravity force | |
892. |
Which of the following fastening devices has its both ends threaded? |
A. | Bolt |
B. | Stud |
C. | Set screw |
D. | Split nut |
Answer» C. Set screw | |
893. |
The activity of pure hydrogen gas at 1000°C and 5 atm pressure |
A. | Is always less than 1 |
B. | Is always greater than 1 |
C. | Can be 5 |
D. | Depends on the choice of the standard state |
Answer» E. | |
894. |
Work done by a/an __________ process is determined by ∫p.dV. |
A. | Adiabatic |
B. | Quasi-static |
C. | Isothermal |
D. | Isentropic |
Answer» C. Isothermal | |
895. |
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 |
Answer» C. Exhaust silencer | |
896. |
Which of the following is categorised as the plastic welding? |
A. | Gas welding |
B. | Electric arc welding |
C. | Forge welding |
D. | None of these |
Answer» D. None of these | |
897. |
Boiling temperature of carbon dioxide at atmospheric pressure is __________ °C. |
A. | -30.5 |
B. | -78.5 |
C. | -183.5 |
D. | -10.5 |
Answer» C. -183.5 | |
898. |
Which of the following materials has the poorest electrical conductivity? |
A. | Carbon |
B. | Aluminium |
C. | Silver |
D. | Stainless steel |
Answer» B. Aluminium | |
899. |
The approximate height of a blast furnace having a useful volume of 2000 m³ is about __________ metres |
A. | 25 |
B. | 35 |
C. | 55 |
D. | 75 |
Answer» D. 75 | |
900. |
Thermistors are used in __________ devices. |
A. | Voltage measuring |
B. | Temperature measuring |
C. | Temperature compensating |
D. | Both B & C |
Answer» E. | |