Question

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Answer 1

Answer:

3) Characteristics of a good fuel

• High calorific value
• High efficiency
• Less residue remain after burning.

4)

1. Ignition Temperature :- It is defined as the least temperature required by an object to start burning.
2. Calorific value :- It refers to how much an object or thing can be used until it get completed.
3. Inflammable Substances :- The substances which can burn even at a very low temperature are called inflammable substances.
4. Combustion:- When an object burns in the presence of oxygen it is called combustion of that material.

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Answer 2

Answer:

Hi dear...

3) Characteristics of a good fuel include low ignition temperature and high calorific value. A good fuel also has a uniform and moderate rate or velocity of combustion. Good fuel should be easy to store and handle, lower ash content, lower moisture content and does not produce harmful gases.

4) a) Ignition temperature is the lowest temperature at which a combustible substance when heated (as in a bath of molten metal) takes fire in air and continues to burn. — called also autogenous ignition temperature. — compare fire point.

b) Calorific value is the energy contained in a fuel or food, determined by measuring the heat produced by the complete combustion of a specified quantity of it. This is now usually expressed in joules per kilogram.

c) The substances which have very low ignition temperature and can easily catch fire with a flame are called inflammable substances.

d) Combustion is the process of burning something.

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