Question

Inflammable substances have an ignition temperature:
A. \[more\text{ }than\text{ }{{100}^{\circ }}C\]
B. \[less\text{ }than\text{ }{{100}^{\circ }}C\]
C. \[more\text{ }than\text{ }{{200}^{\circ }}C\]
D. \[less\text{ }than\text{ }{{200}^{\circ }}C\text{ }to\text{ }{{350}^{\circ }}C\]

Answer 1

Hint: As the name suggests, ignition temperature is the lowest temperature at which combustible substances catch fire. As we also know inflammable means that substance is capable of bursting into flames without the need for any ignition.

Complete step by step answer:
Ignition temperature is also defined as the minimum temperature at which a combustible substance (for example gas) must be heated before burning in the absence of an external source of ignition.
Inflammable substances are substances which are having very low ignition temperature and at the same time undergo combustion such as petrol, alcohol, aerosol sprays, etc.
Therefore, based on the definition of ignition temperature it is concluded that the correct option is (B).

Additional information:
At high-temperature burning or combustion of fuel is an exothermic redox chemical reaction in which fuel is reductant and atmospheric oxygen is an oxidant , it is reduced, and oxidant oxidizes other compounds.
Combustion doesn’t always mean fire but during the process of combustion, the flame is an indicator of reaction.

Note: Remember, don’t confuse an exothermic reaction with an endothermic reaction. As the name suggests, an exothermic reaction means ‘Exo’ meaning releases and ‘thermic’ means heat. So, the reaction in which there is a release of heat with or without light is called an exothermic reaction. While an endothermic reaction means ‘endo’ meaning within and ‘thermic’ meaning heat. Thus, an endothermic process requires or absorbs thermal energy from its surroundings usually in the form of heat.