Fuels and Combustion MCQs

Question 1

Pick out the wrong statement.

Accepted Answer

LPG is lighter than air

Answer

Main constituents of LPG are propane and butane

Answer

C.V. of natural gas is about 10000 kcal/Nm 3

Answer

C.V. of LPG is about 26000 kcal/Nm 3 (11500 kcal/kg)

Question 2

Which of the following fuel gases will require maximum amount of air for combustion of 1 Nm 3 gas?

Accepted Answer

Natural gas

Answer

Blast furnace gas

Answer

Producer gas

Answer

Water gas

Question 3

Coke oven gas is stripped of its H 2 S and mercaptans content by

Accepted Answer

Adsorption on bog iron bed

Answer

Absorption in wash oil

Answer

Bubbling it through dilute sulphuric acid

Answer

Adsorption on silica gel

Question 4

Which of the following has the highest flame speed?

Accepted Answer

H 2

Answer

CO

Answer

CH 4

Answer

C 2 H 6

Question 5

The cuprous chloride used in orsat apparatus can absorb

Accepted Answer

All of the above

Answer

Only CO

Answer

Both CO and CO 2

Answer

Both CO and O 2

Question 6

The pyragallol solution used in orsat apparatus can absorb

Accepted Answer

Both O 2 and CO 2

Answer

Only O 2

Answer

Both O 2 and CO

Answer

All of the above

Question 7

C.V. (kcal/Nm 3 ) of gaseous fuels __________ with increase in molecular weight.

Accepted Answer

May increase or decrease, depends on combustibles

Answer

Decreases

Answer

Increases

Answer

Remains constant

Question 8

The calorific value of natural gas is about __________ kcal/Nm 3 .

Accepted Answer

10,000

Answer

2,500

Answer

25,000

Answer

35,000

Question 9

Calorific value of wood gas is about __________ kcal/Nm 3 .

Accepted Answer

3300

Answer

1500

Answer

5400

Answer

8500