Explore topic-wise MCQs in Engineering.

Refractory bricks with lower permeability is produced by using

Orlan fibre which is used as a wool sub stitute is

Starting material for the production of SBR is

Density of high density polythene is about __________ gm/c.c.

Thiokol is nothing but

Styrene butadiene rubber (SBR) as compared to natural rubber has

Which of the following polymers has the tendency of decomposing before melting ?

Vinyl flooring is done using __________ sheets.

Which of the following polymers belong to the class of formaldehyde resin ?

Trade name of __________ is neoprene.

SBR is produced by the copolymerisation of butadiene & styrene by employing emulsion polymerisation. The weight ratio of styrene and butadiene is maintained at

Transistor parts and refrigerator components are normally made of

Fillers such as zinc oxide and carbon black are added to the crude natural rubber before vulcanisation in order to improve its

The organic acid monomer in nylon 66 is

Neoprene which is used for making shoe heels & belts is superior to natural rubber in its stability to aerial oxidation and resistance to oils & other solvents. The monomer used for making neoprene is

Dacron (or terylene) fibres as compared to nylon fibres have

Which of the following low molecular weight (<10⁴ ), soft & waxy polymer is used in chewing gum ?

The main use of butadiene is

Mastication of rubber means

Reaction of dimethyl terephthalate (DMT) and ethylene glycol produces

Tubeless tyres are made of __________ rubber, which is a co-polymer of isoprene & isobutylene.

Zeigler - Natta catalyst (AlR₃ - AlCl₃) is used in the polymerisation of

Due to its excellent permeability to air/gas and oxidation resistance, the tubes of automobile tyres is made of

90% of the caprolactum is converted to nylon-6 on its condensation polymerisation in the reactor maintained at a temperature of __________ C.

Out of all the elastomers, natural rubber has the longest elongation range & flexibility of the order of __________ percent.

Hydrogen content of coke oven gas is __________ percent.

Ammonium nitrate (a fertiliser) is coated with limestone powder to

Si percentage in silica refractories used in the walls of coke oven is about

Silica bricks are attacked by basic slags at high temperature. Which of the following is not used solely as a binding material?

Cold crushing strength of refractories depends upon its

High thermal conductivity of a refractory material is not important, when it is to be used in the

Maximum safe working temperature for fireclay bricks is about __________ C.

Which is not an alumino-silicate refractory?

Permeability of bricks is a measure of the

With increase in the density of silica refractories, its

Electrical resistor bars are made of

PCE value (Segar cone) of superduty refractories is more than 33, which is equivalent to a temperature of __________ C.

Addition of zircon to silica refractory brick improves its

Thermal spalling mainly occurs during __________ of furnaces.

Pure bauxite is the best raw material for the manufacture of high alumina refractories, in which maximum alumina content can be as high as __________ percent.

Which of the following is not an acidic refractory ?

Insulating refractories should have

Fireclay bricks is not used for lining the

Refractoriness under loads (RUL) is quite close to the fusion temperature (PCE) for __________ bricks.

Tar bonded dolomite bricks

Which is the most stable crystalline form of silica at room temperature ?

Silica refractories

Action of phosphoric acid on rock phosphate produces

Red phosphorous is changed into white phosphorous by

Two gas based fertiliser plants are located in