1232 + Mcqs in Material Science Page 9 McqOptions

401.	in cathodic protection, the commonly used sacrificial anode is
A.	al
B.	mg
C.	zn
D.	all of the above
Answer» E.

Discussion

402.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â is a type of cathodic protection to prevent corrosion
A.	sacrificial anodic or galvanic protection
B.	impressed current cathodic protection
C.	both a and b
D.	none of th e above
Answer» D. none of th e above

Discussion

403.	in corrosion prevention, the metal to be protected from corrosion is forced to behace like cathode in protection method
A.	anodic
B.	cathodic
C.	both a and b
D.	none of the above
Answer» C. both a and b

Discussion

404.	in use of speacial alloys, alloying with Â Â Â Â Â Â Â Â Â Â Â Â Â increases corrosion resistance of brasses and
A.	cr
B.	ni
C.	both a and b
D.	tin
Answer» E.

Discussion

405.	in use of special alloys, for cast irons, addition of increases the corrosion resistance
A.	cr
B.	ni
C.	si
D.	all of the above
Answer» E.

Discussion

406.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â method of corrosion prevention has widely ued in controlling the corrosion of refinery equipments
A.	deactivation
B.	dehumidifica tion
C.	alkaline neutralizatio n
D.	dearation
Answer» D. dearation

Discussion

407.	in use of speacial alloys, alloying of Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â with iron increase corrosion resitance
A.	cr
B.	ni
C.	both a and b
D.	tin
Answer» D. tin

Discussion

408.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â substance is used in alkaline neutralization to prevent corrosive effect of environment
A.	nh3
B.	naoh
C.	lime
D.	all of the above
Answer» E.

Discussion

409.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â method is used to prevent the corroive environmnet by neutralising the acidic character of corrosive conditions
A.	deactivation
B.	dehumidifica tion
C.	alkaline neutralizatio n
D.	dearation
Answer» D. dearation

Discussion

410.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â method of corrosive prevention is useful only in closed areas like air conditioned shops, laboratories, computer rooms etc.
A.	deactivation
B.	dehumidifica tion
C.	alkaline neutralizatio n
D.	dearation
Answer» C. alkaline neutralizatio n

Discussion

411.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â substance which absobe moisture on its surface is used in dehumidification technique for midifiaction of corrosive environment
A.	alumina
B.	silica gel
C.	both a and b
D.	none of the above
Answer» D. none of the above

Discussion

412.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â chemical is added during deactivation technique to modify corrosive environment
A.	sodium sulphite
B.	hydrazine hydrrate
C.	both a and b
D.	none of the above
Answer» D. none of the above

Discussion

413.	in modification of corrosive environment, during technique, certain chemicals are added which combine rapildy with oxygen in acquous solution and reduce
A.	deaeration
B.	deactivation
C.	dehumidifica tion
D.	all of the above
Answer» C. dehumidifica tion

Discussion

414.	in modification of corrosion environment, Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â technique resuces the moisture content of air in such a way that moisture should not condense on the metal surface causing corrosion
A.	deaeration
B.	deactivation
C.	dehumidifica tion
D.	all of the above
Answer» D. all of the above

Discussion

415.	in modification of corrosive environment, in oxygen concentrated cell, the technique of removel of oxygen from acqueous environmnet to reduce corrosion is called as
A.	deaeration
B.	deactivation
C.	dehumidifica tion
D.	all of the above
Answer» B. deactivation

Discussion

416.	modification of corrosive environment is done by technique
A.	deaeration
B.	deactivation
C.	dehumidifica tion
D.	all of the above
Answer» E.

Discussion

417.	in modification of corrosive environment, the corrosive nature of environment is reduced by
A.	removing the harmful components in the environment
B.	neutralising the effect of corrosive constituents of environment
C.	both a and b
D.	none of the above
Answer» D. none of the above

Discussion

418.	during design and fabriaction of the component, a good design should have Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â properties
A.	no crevices between adjacent areas
B.	free drainage and easy washings
C.	no chance for differential aeration corrosion
D.	all of the above
Answer» E.

Discussion

419.	during design and fabrication of component, Â Â Â Â Â Â Â Â Â Â Â Â type of joints should be used
A.	welded
B.	bolted
C.	riveted
D.	all of the above
Answer» B. bolted

Discussion

420.	during design and fabrication of the pipe and tanks, sharp bends and corners should be avoided because they form
A.	stagnant areas
B.	accumulation of solids
C.	both a and b
D.	none of the above
Answer» D. none of the above

Discussion

421.	during design and fabrication of the component, should be considered
A.	avoid the contact of dissimilar metals in the presence of
B.	when two dissimilar metals are to be in contact, anodic
C.	proper fabrication should be done to avoid
D.	all of the above
Answer» E.

Discussion

422.	metarials with characteristics have higher corrosion resistance
A.	purity
B.	coarse grained
C.	smooth surface
D.	all of the above
Answer» E.

Discussion

423.	the choice of metal or an alloy for any application depends on factors like
A.	cost
B.	mechanical properites
C.	availability of material
D.	all of the above
Answer» E.

Discussion

424.	following points are considered while selecting the material for a particular application
A.	metals at anodic end of electrochemi cal series have more corrosion resistance than those at cathodic end
B.	pure metals have more corrosion resistabce than the impure one; but pure metals have inadequate mechanical strength
C.	use of single metal be preferred
D.	all of the above
Answer» E.

Discussion

425.	according to principles usedin control and preventaion of design, the various methods (techniques) are classified as
A.	modification of corrosiove environment
B.	use of special alloys
C.	application of protective coatings
D.	all of the above
Answer» E.

Discussion

426.	in case of steels, the raection between hydrogen and carbon forms methane which causes intergranular carcking, fissuring or blistering is known as
A.	hydrogen embrittleme nt
B.	temper embrittleme nt
C.	hydrogen attack
D.	none of the above
Answer» D. none of the above

Discussion

427.	HIgh temperature phenomena associated with hydrogen is known as
A.	hydrogen embrittleme nt
B.	temper embrittleme nt
C.	hydrogen attack
D.	none of the above
Answer» D. none of the above

Discussion

428.	low temperature phenomena associated with hydrogen is known as
A.	hydrogen embrittleme nt
B.	temper embrittleme nt
C.	hydrogen attack
D.	none of the above
Answer» B. temper embrittleme nt

Discussion

429.	in hydrogen embrittlement if the pressure of molecular hydrogen is greater than the ultimate strength of the material
A.	then the component becomes brittle
B.	then the component will fail
C.	any one of above
D.	none of the above
Answer» C. any one of above

Discussion

430.	in hydrogen embrittlement if the pressure of molecular hydrogen is greate rhan the yield strength of the material
A.	then the component becomes brittle
B.	then the component will fail
C.	both a and b
D.	none of the above
Answer» B. then the component will fail

Discussion

431.	because of diffusion of hydrogen into the metal, the metal becomes brittle that leads to failure of the component is knowna as
A.	hydrogen embrittleme nt
B.	temper embrittleme nt
C.	both a and b
D.	none of the above
Answer» B. temper embrittleme nt

Discussion

432.	hydrogen embrittlement
A.	it is a low temperature phenomenon
B.	it is a high temperature phenomenon
C.	not related with the temperature
D.	none of the above
Answer» B. it is a high temperature phenomenon

Discussion

433.	corrosion fatigue can be reduce by
A.	the treatment of corrosing medium
B.	the surafce protection of metal
C.	the nitriding of steels
D.	all of the above
Answer» E.

Discussion

434.	combined action of corrosion and repeated cyclic loading is called as
A.	pitting corrosion
B.	stress corrosion cracking
C.	cavitation corrosion
D.	corrosion fatigue
Answer» E.

Discussion

435.	the resistance of material to high temperature corrosion can be increased by
A.	addition of inhibitors
B.	addition of metals as alloying elements in metal which has good
C.	both a and b
D.	none of the above
Answer» D. none of the above

Discussion

436.	the components like heat exchanger are prone to
A.	pitting corrosion
B.	cavitation corrosion
C.	high temperature corrosion
D.	none of the above
Answer» D. none of the above

Discussion

437.	rotating pumps, valves are prone to
A.	pitting corrosion
B.	cavitation corrosion
C.	both a and b
D.	none of the above
Answer» D. none of the above

Discussion

438.	small anodic area and large cathod is observed in
A.	pitting corrosion
B.	cavitation corrosion
C.	both a and b
D.	none of the above
Answer» D. none of the above

Discussion

439.	cavitation corrosion can be miminized by
A.	using suitable hydraulic design
B.	using high strength corrosion resistant alloys
C.	using protective coatings
D.	all of the above
Answer» E.

Discussion

440.	due to collapse of vapours on walls of pipes it leads
A.	pitting corrosion
B.	stress corrosion cracking
C.	cavitation corrosion
D.	crevice corrosion
Answer» D. crevice corrosion

Discussion

441.	if a liquid passes from low pressure to high pressure region the type of corrosion is known as
A.	pitting corrosion
B.	stress corrosion cracking
C.	cavitation corrosion
D.	erosion corrosion
Answer» D. erosion corrosion

Discussion

442.	the combined effect of abrading action of turbulent flow of gases, vapours liquids and mechanical rubbing action of solids over a
A.	pitting corrosion
B.	stress corrosion
C.	intergranular corrosion
D.	crevice corrosion
Answer» B. stress corrosion

Discussion

443.	the type of corrosion which take place in nut and bolt fittings is
A.	pitting corrosion
B.	stress corrosion cracking
C.	crevice corrosion
D.	intergranular erosion
Answer» D. intergranular erosion

Discussion

444.	erosion corrosion caused by
A.	the breakdown of preotective film at spot of impingement
B.	turbulent flow of gases
C.	both a and b
D.	none of the above
Answer» D. none of the above

Discussion

445.	due to difference in oxygen concentration at two different points it leads to
A.	pitting corrosion
B.	stress corrosion cracking
C.	intergranular corrosion
D.	erosion corrosion
Answer» E.

Discussion

446.	at a juction of two metals exposed to a corrosive environment is leads to
A.	pitting corrosion
B.	stress corrosion cracking
C.	intergranular corrosion
D.	crevice corrosion
Answer» E.

Discussion

447.	for a given metal or alloy, the possibility of stress corrosion depends upon
A.	the oxygen content and ph value of electrolyte
B.	the oxygen content
C.	ph value of electrolyte
D.	none of the above
Answer» B. the oxygen content

Discussion

448.	Cu and its alloys crack in ammonia and environments containing mercury
A.	pitting corrosion
B.	stress corrosion cracking
C.	intergranular corrosion
D.	erosion corrosion
Answer» D. erosion corrosion

Discussion

449.	carbon steels crack in nitrate solutions is a type of
A.	pitting corrosion
B.	stress corrosion cracking
C.	intergranular corrosion
D.	erosion corrosion
Answer» D. erosion corrosion

Discussion

450.	the critical level of stress depends uopn Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â factor
A.	composition of alloy
B.	grain size, microstructur e and geometry of the component
C.	surface finish of the component
D.	all of the above
Answer» E.

Discussion

Explore topic-wise MCQs in Electrical Engineering.

in cathodic protection, the commonly used sacrificial anode is

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â is a type of cathodic protection to prevent corrosion

in corrosion prevention, the metal to be protected from corrosion is forced to behace like cathode in protection method

in use of speacial alloys, alloying with Â Â Â Â Â Â Â Â Â Â Â Â Â increases corrosion resistance of brasses and

in use of special alloys, for cast irons, addition of increases the corrosion resistance

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â method of corrosion prevention has widely ued in controlling the corrosion of refinery equipments

in use of speacial alloys, alloying of Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â with iron increase corrosion resitance

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â substance is used in alkaline neutralization to prevent corrosive effect of environment

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â method is used to prevent the corroive environmnet by neutralising the acidic character of corrosive conditions

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â method of corrosive prevention is useful only in closed areas like air conditioned shops, laboratories, computer rooms etc.

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â substance which absobe moisture on its surface is used in dehumidification technique for midifiaction of corrosive environment

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â chemical is added during deactivation technique to modify corrosive environment

in modification of corrosive environment, during technique, certain chemicals are added which combine rapildy with oxygen in acquous solution and reduce

in modification of corrosion environment, Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â technique resuces the moisture content of air in such a way that moisture should not condense on the metal surface causing corrosion

in modification of corrosive environment, in oxygen concentrated cell, the technique of removel of oxygen from acqueous environmnet to reduce corrosion is called as

modification of corrosive environment is done by technique

in modification of corrosive environment, the corrosive nature of environment is reduced by

during design and fabriaction of the component, a good design should have Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â properties

during design and fabrication of component, Â Â Â Â Â Â Â Â Â Â Â Â type of joints should be used

during design and fabrication of the pipe and tanks, sharp bends and corners should be avoided because they form

during design and fabrication of the component, should be considered

metarials with characteristics have higher corrosion resistance

the choice of metal or an alloy for any application depends on factors like

following points are considered while selecting the material for a particular application

according to principles usedin control and preventaion of design, the various methods (techniques) are classified as

in case of steels, the raection between hydrogen and carbon forms methane which causes intergranular carcking, fissuring or blistering is known as

HIgh temperature phenomena associated with hydrogen is known as

low temperature phenomena associated with hydrogen is known as

in hydrogen embrittlement if the pressure of molecular hydrogen is greater than the ultimate strength of the material

in hydrogen embrittlement if the pressure of molecular hydrogen is greate rhan the yield strength of the material

because of diffusion of hydrogen into the metal, the metal becomes brittle that leads to failure of the component is knowna as

hydrogen embrittlement

corrosion fatigue can be reduce by

combined action of corrosion and repeated cyclic loading is called as

the resistance of material to high temperature corrosion can be increased by

the components like heat exchanger are prone to

rotating pumps, valves are prone to

small anodic area and large cathod is observed in

cavitation corrosion can be miminized by

due to collapse of vapours on walls of pipes it leads

if a liquid passes from low pressure to high pressure region the type of corrosion is known as

the combined effect of abrading action of turbulent flow of gases, vapours liquids and mechanical rubbing action of solids over a

the type of corrosion which take place in nut and bolt fittings is

erosion corrosion caused by

due to difference in oxygen concentration at two different points it leads to

at a juction of two metals exposed to a corrosive environment is leads to

for a given metal or alloy, the possibility of stress corrosion depends upon

Cu and its alloys crack in ammonia and environments containing mercury

carbon steels crack in nitrate solutions is a type of

the critical level of stress depends uopn Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â factor