Chemical Engineering Basics MCQs

Question 1

Pick out the wrong statement.

Accepted Answer

Crushing load or columns is less than the buckling load

Answer

The equivalent stiffness of two springs (of equal stiffness 'S') in series is $$\frac{{	ext{S}}}{2}$$ while in parallel is 2S

Answer

For a helical spring, deflection is proportional to D 3 (D = mean coil diameter) or d 4 (d = wire diameter)

Answer

Modulus of resilience is proportional to (stress at elastic limit) 2

Question 2

The substance used as a smoke screen in warfare is

Accepted Answer

SiCl 4

Answer

C 2 H 2

Answer

P 2 O 5

Answer

PCl 5

Question 3

Saturated steam at a pressure of 25 kg/cm 2 is throttled to attain 5 kg/cm 2 . Then the outcoming steam will be

Accepted Answer

Superheated

Answer

Wet

Answer

Saturated

Answer

None of these

Question 4

In Newton's law of viscosity, which states that the shear stress is proportional to the __________ co-efficient of viscosity is called dynamic or absolute viscosity (where, V = velocity, $${{	ext{V}}_{	ext{g}}}$$ = velocity gradient).

Accepted Answer

V g

Answer

V 2

Answer

$$\frac{1}{{{{	ext{V}}^2}}}$$

Answer

$$\frac{1}{{{{	ext{V}}_{	ext{g}}}}}$$

Question 5

Coating thickness in case of galvanising of steel sheet generally corresponds to the deposition of __________ gms of zinc per m 2 of steel strip.

Accepted Answer

120 - 500

Answer

5 - 10

Answer

1000 - 1500

Answer

1500 - 3000

Question 6

Electrolytic reduction cell used for conversion of calcined Al 2 O 3 to Al is a carbon lined furnace operating at 800 - 900°C. The purpose of electric current supplied to the furnace is to

Accepted Answer

Both (B) & (C)

Answer

Achieve very high purity of aluminium (99.9%)

Answer

Keep the electrolyte in liquid condition by the generation of heat

Answer

Electrolytically dissociate alumina

Question 7

The diffusion co-efficient of Ni in Cu at 1000 K is 1.93 x 10 -16 m 2 .S -1 and it is 1.94 × 10 -14 m 2 .S -1 at 1200 K. The activation energy (in k.J.mole -1 ) for the diffusion of Ni in Cu is

Accepted Answer

230

Answer

130

Answer

180

Answer

250

Question 8

Electrical conductivities of semi-conductors are of the order of __________ ohm/cm.

Accepted Answer

10 -3

Answer

10 3

Answer

10 -15

Answer

10 15

Question 9

What happens, when SO 2 is passed through a solution of H 2 S in water?

Accepted Answer

Precipitation of sulphur takes place

Answer

H 2 SO 3 is formed

Answer

Oleum is formed

Answer

None of these