Materials & Construction Mcqs for Chemical - Set 15

1)   Lead pipes are not safe for carrying drinking water, because water, containing dissolved oxygen attacks lead thereby forming poisonous Pb(OH)2. Lead pipes are readily corroded by___________________?

a. Dilute HCl
b. Acetic acid
c. Concentrated H2SO4
d. None of these
Answer  Explanation 

ANSWER: Acetic acid

Explanation:
No explanation is available for this question!


2)   Nickel as a material of construction__________________?

a. Is used as an alloying element for both ferrous & non-ferrous alloys
b. Is paramagnetic below 415° C (its Curie temperature)
c. Diamagnetic
d. Has a body centred cubic (bcc) crystal lattice structure
Answer  Explanation 

ANSWER: Is used as an alloying element for both ferrous & non-ferrous alloys

Explanation:
No explanation is available for this question!


3)   Tin base and lead base alloys are used for bearing materials. Tin compared to lead has lower_________________?

a. Price
b. Corrosion resistance
c. Thermal conductivity
d. Abundant availability
Answer  Explanation 

ANSWER: Abundant availability

Explanation:
No explanation is available for this question!


4)   Glass is corroded by________________?

a. Fluorine (dry or wet)
b. Sulphuric acid
c. Phosphoric acid
d. None of these
Answer  Explanation 

ANSWER: Fluorine (dry or wet)

Explanation:
No explanation is available for this question!


5)   Nickel base alloys with ______________ are known as monel metal?

a. Zinc
b. Tin
c. Copper
d. Molybdenum
Answer  Explanation 

ANSWER: Copper

Explanation:
No explanation is available for this question!


6)   How many atoms are there per unit cell in a body centred cubic lattice system ?

a. 6
b. 5
c. 3
d. 2
Answer  Explanation 

ANSWER: 2

Explanation:
No explanation is available for this question!


7)   Bush bearings are made of______________________?

a. Mild steel
b. Phosphorous bronze
c. White metal alloys
d. None of these
Answer  Explanation 

ANSWER: Phosphorous bronze

Explanation:
No explanation is available for this question!


8)   Presence of cobalt in steel improves its____________________?

a. Cutting ability
b. Corrosion resistance
c. Tensile strength
d. None of these
Answer  Explanation 

ANSWER: Cutting ability

Explanation:
No explanation is available for this question!


9)   A hardness depth of about 3 mm can be achieved by induction hardness in ______________ seconds?

a. 5
b. 100
c. 250
d. 500
Answer  Explanation 

ANSWER: 5

Explanation:
No explanation is available for this question!


10)   Wrought iron is having very high ________________?

a. Hardness
b. Strength
c. Corrosion resistance
d. Susceptibility to changes in its properties by heat treatment
Answer  Explanation 

ANSWER: Corrosion resistance

Explanation:
No explanation is available for this question!


11)   Rotary kilns in cement industry are lined with _____________bricks?

a. Fireclay
b. Silica
c. Lead
d. High alumina & high magnesia
Answer  Explanation 

ANSWER: High alumina & high magnesia

Explanation:
No explanation is available for this question!


12)   Post weld heat treatment is done by____________________?

a. Normalising
b. Stress relieving
c. Tempering
d. Solution annealing
Answer  Explanation 

ANSWER: Stress relieving

Explanation:
No explanation is available for this question!


13)   High speed steel tools retain their hardness upto a temperature of _____________ °C?

a. 500
b. 750
c. 900
d. 1100
Answer  Explanation 

ANSWER: 900

Explanation:
No explanation is available for this question!


14)   When iron is rusted, it is__________________?

a. Converted to a fine powder
b. Reduced
c. Oxidised
d. None of these
Answer  Explanation 

ANSWER: Oxidised

Explanation:
No explanation is available for this question!


15)   Caustic soda is transported in _____________ lined containers ?

a. Glass
b. Nickel
c. Neoprene
d. Either B. or C.
Answer  Explanation 

ANSWER: Either B. or C.

Explanation:
No explanation is available for this question!


16)   _______________ is a donor impurity for semi-conductors ?

a. Boron
b. Antimony
c. Gallium
d. None of these
Answer  Explanation 

ANSWER: Antimony

Explanation:
No explanation is available for this question!


17)   Non-ferrous metals and hard steels do not exhibit a definite yield point, when pulled in the testing machine and hence for these cases, a better measure of their elastic properties is defined by the ______________ stress?

a. Ultimate
b. Yield point
c. Proof
d. None of these
Answer  Explanation 

ANSWER: Proof

Explanation:
No explanation is available for this question!


18)   How many molecules per unit cell are there in a face centred cubic lattice ?

a. 2
b. 4
c. 6
d. 8
Answer  Explanation 

ANSWER: 4

Explanation:
No explanation is available for this question!


19)   ‘Semi steel’ is__________________?

a. Produced by adding 10-20% steel to the cupola charge
b. Stronger than cast iron
c. Both A. and B.
d. Neither A. nor B.
Answer  Explanation 

ANSWER: Both A. and B.

Explanation:
No explanation is available for this question!


20)   Which one occupies the lowermost position in the electromotive series of metals ?

a. Aluminium
b. Noble metals (Ag, Pt, Au)
c. Zinc
d. Alkali metals (K, Na, Li)
Answer  Explanation 

ANSWER: Noble metals (Ag, Pt, Au)

Explanation:
No explanation is available for this question!


21)   Ferric stainless steels compared to austenitic stainless steels________________?

a. Have lower corrosion resistance
b. Are harder to fabricate
c. Are less ductile and hence less suitable for cold pressing
d. All A., B. and C.
Answer  Explanation 

ANSWER: All A., B. and C.

Explanation:
No explanation is available for this question!


22)   Reduction in the grain size reduces the _______________ of the material?

a. Fatigue resistance
b. Tensile strength
c. Creep resistance
d. All A., B. & C.
Answer  Explanation 

ANSWER: Creep resistance

Explanation:
No explanation is available for this question!


23)   ______________ iron is produced, when molten pig iron is allowed to cool gradually?

a. White cast
b. Grey cast
c. Wrought
d. None of these
Answer  Explanation 

ANSWER: Grey cast

Explanation:
No explanation is available for this question!


24)   Sulphuric acid is mixed with ground phosphate rock (to produce phosphoric acid) in a steel digestor lined with__________________?

a. Acidic refractory
b. Rubber
c. Karbate
d. Lead or acid-proof bricks
Answer  Explanation 

ANSWER: Lead or acid-proof bricks

Explanation:
No explanation is available for this question!


25)   Maximum carbon content in cast iron is ______________ percent?

a. 3.8
b. 5.2
c. 4.8
d. 4.3
Answer  Explanation 

ANSWER: 4.3

Explanation:
No explanation is available for this question!


26)   Cast iron is__________________?

a. Used for making shock resisting parts
b. Manufactured in cupola and is brittle
c. Having compressive strength more than its tensile strength
d. All A., B. & C.
Answer  Explanation 

ANSWER: All A., B. & C.

Explanation:
No explanation is available for this question!


27)   Sulphuric acid is mixed with ground phosphate rock (to produce phosphoric acid) in a steel digestor lined with______________?

a. Acidic refractory
b. Rubber
c. Karbate
d. Lead or acid proof bricks
Answer  Explanation 

ANSWER: Acidic refractory

Explanation:
No explanation is available for this question!


28)   Manganese in steel affects its__________________?

a. Ductility
b. Tensile strength
c. Hardness
d. None of these
Answer  Explanation 

ANSWER: Ductility

Explanation:
No explanation is available for this question!


29)   High carbon steel contains more than _____________ percent carbon?

a. 0.5
b. 2.2
c. 2.5
d. 2.8
Answer  Explanation 

ANSWER: 0.5

Explanation:
No explanation is available for this question!


30)   Which of the following has no effect on the carbide forming tendency in steels ?

a. Molybdenum
b. Phosphorus
c. Chromium
d. Vanadium
Answer  Explanation 

ANSWER: Phosphorus

Explanation:
No explanation is available for this question!