Chem Eng Basic Concept Flashcards
The softness or hardness of a grinding wheel depends upon the type & amount of bonding material used. For general purpose cutter grinding __________ grinding wheel is normally used.
aluminium oxide
Tin based white metals are used, where bearings are subjected to
high pressure & load.
Friction factor for fluid flow in pipe does not depend upon the
pipe length.
Chromium molybdenum steel can not be welded using __________ welding.
electrical resistance
A high pressure boiler generates steam at a pressure greater than __________ kg/cm2
80
Evaporative cooling process employs a combination of cooling and humidification in which the
sensible heat is removed and the latent heat is added.
Annealing ofwhite cast iron produces __________ iron.
malleable
Area under the stress-strain curve upto the __________ is referred to as the modulus of resilience.
proportional limit
is the hardest oxide and is hence used where high wear resistance at high temperature is required.
Alumina
A material in which the atoms are arranged regularly in some directions but not in others, is termed as ‘mesomorphous material’; an example of which is
lead
Maximum amount of thermal radiation is emitted at all wavelengths at any specified temperature by a/an __________ body.
grey
In condensers used in thermal power plants, steam is normally used in shell side and cooling water on the tube side, because of the reason that
water velocity can be increased conveniently to increase the overall heat transfer co-efficient because of its lower specific volume compared to steam.
Cobalt - 60 is used as a source of __________ in medical therapy & industrial radiography.
γ-rays
Absolute zero pressure can be attained at a temperature of
0°R
The product out from a cupola is called
cast iron
Phenolic water generated in coke ovens & by-product plant attached to an integrated steel plant containing phenol in concentration of less than 100 mg/litre can be removed by
treating in biological oxygen pond
The widest explosive limit is of __________ , thereby making it the most explosive gas.
acetylene
Polluted water having low BOD are most economically treated in
oxidation ponds
Tri-sodium phosphate is used in boiler water treatment to reduce
caustic embrittlement
The commonest form of iron & manganese found in ground water as pollutant is in the form of their
bi-carbonates
80% less than 200 mesh size particles are called
powder
TLV of ozone (O3) and phosgene (COCl2) in air is __________ ppm.
0.1
Most of the atmospheric air pollutants are present in large quantity in
trophosphere
Pneumoconiosis’ is a disease caused by the inhalation of __________ dust.
coal
The ratio of oxygen available to the oxygen required for stabilisation of sewage is called the
relative stability.
Most efficient and suitable dust removal equipment for removal of flyash from flue gas in a thermal power plant is the
electrostatic precipitator
The main industrial source of emission of hydrogen sulphide air pollutant is
coal based thermal power plants.
Waste/polluted water discharged from electroplating, blast furnace and coal mining industries contain mainly __________ substances.
inorganic
Nitrogen oxides (NOx) is not produced in the __________ industry.
detergent
Oil and grease present in an emulsified state in waste water discharged from industries can be removed by
settling out using chemical reagents.
The amount of chemical coagulant added for treatment of polluted water __________ with increase in temperature of the polluted water to be treated.
decreases
Transition from laminar to turbulent zone in free convection heat transfer is governed by the critical value of
Grashoff number & Prandtl number.
