Deck 4: Fuel and Hydrocarbon

Question 1

When crude oil is heated, then which of the following hydrocarbon is given off first.

A)kerosene
B)gasoline
C)paraffin
D)natural gas.

Answer 1

natural gas.

Question 2

The rating of a diesel engine, with increase in air-intlet temperature, will

A)increase linearly
B)decrease linearly
C)increase parabolically
D)decrease parabolically

Answer 2

decrease linearly

Question 3

A 75 cc engine has following parameter as 75 cc

A)fuel tank capacity
B)lub oil capacity
C)swept volume
D)cylinder volume

Answer 3

swept volume

Question 4

A heat engine utilises the

A)calorific value of oil
B)low heat value of
C)high heat value of oil
D)mean heat value of oil

Question 5

Gaseous-fuel guarantees are based on

A)calorific value of oil
B)low heat value of oil
C)high heat value of oil
D)mean heat value of oil

Question 6

Fuel consumption of diesel engines is not guaranteed at one quarter load because at such low loads

A)the friction is high
B)the friction is unpredictable
C)the small difference in cooling water temperature or in internal friction has a disproportionate effect
D)the engine is rarely operated

Question 7

Polymerisation is a chemical process in which molecules of a compound become

A)larger
B)slowed down
C)smaller
D)liquid

Question 8

Which of the following is the lightest and most volatile liquid fuel

A)diesel
B)kerosene
C)fuel oil
D)gasoline

Question 9

The theoretically correct air fuel ratio for petrol engine is of the order of

A)6 : 1
B)9 : 1
C)12 : 1
D)15 : 1

Question 10

Air fuel ratio for idling speed of a petrol engine is approximately

A)1 : 1
B)5 : 1
C)10:1
D)15 : 1

Question 11

Air fuel ratio at which a petrol engine can not work is

A)8 : 1
B)10 : 1
C)15 : 1
D)20 : 1 and less

Question 12

Advantage of gaseous fuel is that

A)it can be stored easily
B)it can mix easily with air
C)it can displace more air from the engine
D)all of the above

Question 13

Paraffins have molecular structure of

A)chain saturated
B)chain unsaturated
C)ring saturated
D)ring unsaturated

Question 14

Hydrocarbons are decomposed into smaller hydrocarbons by

A)reforming
B)refining
C)cracking
D)polymerization

Question 15

The molecular structure of the straight-run gasoline is changed by

A)cracking
B)reforming
C)reining
D)boiling

Question 16

For SI engines fuels most preferred are

A)aromatics
B)parafins
C)olefins
D)napthenes

Question 17

For CI engine fuels most preferred are

A)napthenes
B)paraffins
C)olefins
D)aromatics

Question 18

Octane number of iso-octane is

A)0
B)30
C)60
D)100

Question 19

Ignition quality of diesel fuel is indicated by its

A)octane number
B)cetane number
C)fash point
D)fire point

Question 20

Flash point of fuel oil is

A)minimum temperature to which1 oil is heated in order to give off inflammable vapours in Sufficient quantity to ignite momentarily when brought in contact with a flame
B)temperature at which it solidifies or congeals
C)temperature at which it catches fire without external aid
D)indicated by 90% distillation temperature, i.e. when 90% of sample oil has distilled off

Question 21

Gasohol is a mixture of

A)90% ethanol + 10% gasoline
B)10% ethanol +90% gasoline
C)40% ethanol + 60% gasoline
D)50% ethanol +50% gasoline

Question 22

Stoichiometric air-fuel ratio of petrol is roughly

A)50:1
B)25:1
C)15:1
D)1:1

Question 23

Venturi in the carburetor results in

A)decrease of air velocity
B)increase of air velocity
C)decrease of fuel flow
D)increase of manifold vacuum