Chapter 6 – Combustion and Flames

Which of the following fuel produces ash on burning:

The zone of a flame used by goldsmith for melting gold and silver is:

Can the process of rusting he called combustion ?

Is heat and light produced by Sun a combustion process?

Heat and light produced in the sun is by:

Ignition temperature is the:

Which of them can be easily burnt with the help of a matchstick?

A mgtchstjck does not catch fire on its own at room temperature because its:

Which of the following gas extinguishes fire:

Combustion that takes place at a very fast rate is called:

The coldest zone of candle is:

Smoke contains:

The colour of the non-luminous zone is:

Which of the following fuel has the highest calorific value:

The fuel which replaces use of diesel and petrol as fuels in automobiles is:

Which of following does not produce flame on burning:

Which of the following is best fuel for automobiles:

which of the following causes global warming:

The unit of calorifie virtue is:

The hottest zone of candle fleme is:

A chemical process in which a substance reacts with oxygen to give off heat is called.

Which of the following burns with flame:

Magnesium burns in air to form

Which of the following substance is not combustible:

In which of the following conditions combustion takes place:

Which of the following is smoke free fuel:

Coal mainly contains:

Which poisonous gas is formed as a result of incomplete combustion ?

The natural solid fuel is:

Which of the following give us pollution free environment on burning: