_________ fuels occur in the same form as they occur in nature.
Primary
Secondary
Gaseous
Non-renewable
The efficiency of the fuel is judged by its _________.
Calorific value
Burning time
Energy generated
None of these
On the complete combustion of methane we get a material that is
Acidic
Basic
Neutral
Solid
The heat produced by burning 1 g of fuel completely is known as:
heat capacity
calorific value
vapour density
boiling point
Select the quality that a good fuel should possess.
A high calorific value
A low calorific value
It should burn too fast
It should burn too slow
Types of combustion are:
rapid
spontaneous, rapid and explosive:
explosive
spontaneous
During an exothermic process _________ is released
Light
Heat
Oxygen
Air
Combustion is a _____ reaction accompanied by heat and light.
reduction
redox
substitution
oxidation
While to put out a fire by throwing sand, which of the following process does sand do?
Break the contact of the combustible substance
Stop the supply of the supporter of combustion
Cool the substance below its ignition temperature
Bio gas is a secondary fuel obtained from .
Coal
Animal dung
Petrol
Wood
