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Worksheetswater technology BME
Total questions: 16
Worksheet time: 8mins
Hardness in water is caused by the presence of:
Sodium chloride
Sodium carbonate
Calcium chloride
Potassium nitrate
Permanent hardness in water is caused by the presence of:
Calcium bicarbonate
Magnesium sulfate
Both of them
None of them
Water is hard when it contains:
Acid solution
Precipitate in suspension
Dissolved sodium salts
Dissolved Ca and Mg salts
Which of the following does not cause the permanent hardness in water?
Nitrates
Sulphates
Chlorides
Bicarbonates
In _____________ when the water is heated then the soluble salts turns into insoluble ones and removed by filtration.
Temporary hardness
Permanent hardness
Non-carbonate
Non-alkaline
Scale formation in boilers causes
no loss of heat
wastage of heat
increase in efficiency
none of the above
Hard water is unfit for use in boilers for “steam raising” because
its boiling point is higher
steam generated at a high pressure
it leads to scale formation inside the boiler
water undergoes decomposition in to oxygen and hydrogen.
What is the function of a boiler?
to heat water to make steam
to heat water to make spaghetti
to transform liquid into a mist
to mix air and fuel
deposits of calcium and magnesium carbonates on the boiler heating surface cause ___
scale
oxygen pitting
caustic embrittlement
carryover
priming is dangerous and can lead to ___ hammer
steam
water
gas
air
boiler water is treated to prevent...
scale
oxygen pitting
caustic embrittlement
all of the above
boiler water having high alkalinity could develop ___
acidic corrosion
oxygen pitting
caustic embrittlement
warping
Coagulants help in the settling of
suspended impurities only
fine suspended matter only
colloidal particles only
both (B) and (C)
