Questions

A chemical reaction in which involves the absorption of heat from the environment is called a Endothermic reaction. 

Examples : Dissolving ammonium chloride in water, photosynthesis, melting ice cubes, mixing of potassium chloride with water,...

In the contrast, chemical reactions involving release of heat are known as exothermic reactions.

Examples : Combustion, coal is burnt, mix of CaO with water,...

Iron reacts with oxygen in the presence of moisture or water to form a red oxide called rust and the reaction involved is called as Redox reaction.

The Indian Navy operates three operational Commands. They are

1. Western Naval Command - Mumbai

2. Eastern Naval Command  - Vishakhapatnam

3. Southern Naval Command - Kochi

The galapagos finches are an excellent example of speciation which means the formation of distinct species in the course of evolution.