CHEMICAL ENGINEERING

Question: Heating of ferromagnetic materials to a temperature above Curie temperature makes it
[A].

insulator for heat & electricity transmission.

[B].

ferritic.

[C].

behave like paramagnetic materials.

[D].

superconductor.

Answer: Option C

Explanation:

No answer description available for this question.

Question: All the atoms of the world comprise of electrons, proton & neutron except that of __________ atom in which neutron is absent.
[A].

deuterium

[B].

hydrogen

[C].

neon

[D].

helium

Answer: Option B

Explanation:

No answer description available for this question.

Question: A semi-conductor is damaged & behaves like a conductor, on passing a strong electric current through it, because it heats up the crystals & breaks the covalant bonds resulting in __________ electrons.
[A].

lack of free

[B].

excess of

[C].

decrease in

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: Metalloids
[A].

are good conductor of heat & electricity.

[B].

act as electron donors with metals & as electron acceptor with non-metals.

[C].

are not necessarily solids at room temperature.

[D].

are compounds that exhibit both metallic & non-metallic properties to some extent and are exemplified by elements like germanium, silicon & boron.

Answer: Option D

Explanation:

No answer description available for this question.

Question: Ferromagnetic material owe their properties to __________ inner sub-shells.
[A].

completely filled

[B].

partially filled

[C].

equally filled

[D].

vacant

Answer: Option B

Explanation:

No answer description available for this question.

Question: Electrical conductivities of semi-conductors are of the order of __________ ohm/cm.
[A].

10-3

[B].

103

[C].

10-15

[D].

l015

Answer: Option A

Explanation:

No answer description available for this question.

Question: Out of the following, the lowest packing of atoms exists in __________ crystal lattice structure.
[A].

hexagonal close, packed (hcp)

[B].

face centred cubic (fcc)

[C].

body centred cubic (bcc)

[D].

simple cubic

Answer: Option D

Explanation:

No answer description available for this question.

Question: Ceramic compounds as compared to metallic compounds
[A].

crystallise faster.

[B].

resist greater tensile stress at room temperature.

[C].

have higher melting temperature.

[D].

are better conductor of electricity at higher temperature.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Consumable electrodes are used in the __________ welding.
[A].

gas

[B].

arc

[C].

thermit

[D].

resistance

Answer: Option B

Explanation:

No answer description available for this question.

Question: Laser welding is widely employed in the __________ industries.
[A].

electronic

[B].

structural

[C].

process

[D].

heavy

Answer: Option A

Explanation:

No answer description available for this question.