Chemical Engineering - Chemical Engineering Basics
Exercise :: Chemical Engineering Basics - Section 18
16.
Coke is added in the blast furnace to
A.
reduce & melt the iron ore. B.
increase the fluidity of slag. C.
remove sulphur & phosphorus from molten metal. D.
none of these.
Answer: Option A
Explanation:
17.
A balanced draught boiler furnace employs __________ draught fan.
A.
induced B.
forced C.
both 'a' & 'b' D.
neither 'a' nor 'b'
Answer: Option C
Explanation:
18.
Aluminium oxide (an abrasive) is used for grinding
A.
ceramics B.
high speed steel C.
cemented carbide D.
none of these
Answer: Option B
Explanation:
19.
In a casting, cold shut defect is caused by
A.
low pounhg temperature. B.
melt-mould reactions. C.
faulty gating system. D.
very low mould permeability.
Answer: Option A
Explanation:
20.
Even minute presence of impurities in copper impairs its electrical conductivity seriously. Electrolytic refinning of blister copper is resorted to, when
A.
cheap electricity is available. B.
the precious metal content of copper is high. C.
there is a demand for ultrapure (99.99%) electrolytic copper. D.
all (a), (b) & (c).
Answer: Option D
Explanation: