Combustion and ...

A substance which reacts with oxygen giving heat is called a combustible substance. Which one of the following is a combustible substance?

Which one of the following has the highest calorific value?

Magnesium ribbon on burning in air produces

Which of the following is not a combustible substance?

The substance that does not burn with flame is

On placing an inverted tumbler over a burning candle, the flame extinguishes after some time. This is because of non-availability of

If a person’s clothes catches fire, the best way to extinguish the fire is to

The substance expected to have the highest ignition temperature out of the following is

Choose the correct statement about inflammable substances from the following. They have

Choose the incorrect statement from the following. Forest fires are usually due to

The calorific value of a fuel is expressed in a unit called

In villages, people use wood as fuel because

Which among the following is considered as the cleanest fuel?

Choose the incorrect statement from the following.

A good fuel is one which

Shyam was cooking potato curry on a chulha. To his surprise he observed that the copper vessel was getting blackened from outside. It may be due to