Which one is neutral in character?
N2O4
N2O
N2O5
N2O3
Correct Answer :
B. N2O
Related Questions
Presence of nickel & chromium in steel does not raise its
Elastic limit
Machining properties
Ductility
Resilience
Diffusion co-efficient of a metal in a solid solution depends upon its
Composition
Temperature
Both (A) & (B)
Neither (A) nor (B)
Maximum hardenability of steel depends upon its
Chemical composition
Carbon content
Grain size
Alloying elements content
Which of the following contributes maximum as main source of sulphur in the blast furnace charge?
Sinter
Coke
Iron ore
Limestone
The material used for coating the welding electrode is termed as the
Flux
Slag
Protective layer
Binder
Which of the following is an example of cathodic protection of metals against corrosion?
Painted steel
Galvanised iron
Case hardened steel
Lead lined reactor
Percentage of differential pressure lost in a Venturimeter with a tapering of 15° may be about
1
10
25
50
Thermit welding is categorised as the __________ welding.
Forge
Fusion
Resistance
Arc
Hot & cold working of material causes its __________ deformation.
Visco-elastic
Isotropic
Elastic
Plastic
The maximum thickness of the metal which can be welded using ultrasonic welding is __________ mm.
0.5
3
10
25
Water flow in the river during flood can be categorised as the __________ flow.
Unsteady uniform
Unsteady non-uniform
Steady uniform
Steady non-uniform
Materials having resistivity ranging from 1 to 100 ohm. cm is termed as
Conductor
Insulator
Semi-conductor
None of these
Lead is poured into the joint between two- __________ pipes.
Mild steel
Concrete
Cast iron
Asbestos cement
Vibration upto 100 kilo hertz can be most accurately measured by a __________ type accelerometer.
Preloaded spring
Piezoelectric
Bonded strain gauge
None of these
Pick out the wrong statement.
For a pressure vessel to be classified as 'thin vessel', the ratio of wall thickness to mean radius is less than 0.1
For calculating forces and efficiency of riveted joint, either rivet diameter or rivet hole diameter is used in case of pressure vessel and in structural work
Longitudinal joint is normally made butt joint to maintain the circularity of the vessel
Maximum diameter of the opening provided in a pressure vessel, which does not require any compensation is 200 mm
Which of the following is not an ore of copper?
Cryolite
Azurite
Chalcopyrite
Malachite
Angular displacement can be measured suitably by a
Shaft encoder
Linear variable differential transducer (LVDT)
Stroboscope
Tachometer
Which of the following processes follows the hardening process for reducing the hardening strains & increasing the toughness of the steel part?
Anodising
Tempering
Carburising
Annealing
If a solid is compressed adiabatically in its elastic range, its __________ remains constant
Internal energy
Enthalpy
Entropy
Temperature
In an eutectic system, two elements are completely
Soluble in solid state
Insoluble in liquid state
Insoluble in both solid & liquid state
Soluble in liquid state
Electrometallurgical methods of metal extraction is normally used for those metals
Whose oxide/ore is not reduced by carbon
Which fall in the category of alkali & alkaline earth metals
Which stands higher in the electrochemical series of the metal
All (A), (B) & (C)
Speed of a submarine in deep sea & that of an aeroplane is measured by a/an
Pitot tube
Hot wire anemometer
Rotameter
Stroboscope
Silicon percentage in silicon steel used for electrical equipments is about
1
4.0
8
14
Melting point & boiling points of liquid oxygen are respectively - 218.8°C & - 183°C, while the same for liquid nitrogen is - 210°C & - 195.8°C respectively. The difference in melting points of liquid oxygen & liquid nitrogen is not equal to 8.8
°C
°F
°K
°R
A solid aluminium ball, when quenched in a water bath maintained at 40°C, cools down from 550°C to 450°C in 20 seconds. The expected temperature of the ball after next 20 seconds may be about __________ °C.
370
340
320
300
Volume of blast furnace slag is about __________ times the volume of hot metal (pig iron) of the same weight
1.5
3
5
7
Metal shots used in shot blasting are made of
Stellite
Steel
Bronze
Lead
Boiling point of water gets lowered at high altitudes (e.g., hills), because
Temperature is low
Atmospheric pressure is low
Atmospheric pressure is high
None of these
Pick out the wrong statement about the machinability of metals. Machinability of a metal
Decreases with increase in strain hardening tendencies
Decreases with increase in hardness, in general
Depend on the composition, microstructure and physical & mechanical properties
Decreases with increases in tensile strength & decrease in grain size
Ammonia gas can be dried by
PCl5
Quick lime
CaCl2
Concentrated H2SO4