Reactions
Exothermic — তাপোৎসর্মী
Quick answer
An exothermic reaction releases heat to its surroundings, warming the container it happens in.
Definition
In an exothermic reaction the products hold less energy than the reactants did, so the spare energy streams out as heat or light and the surroundings warm up — the thermometer climbs. Burning fuels, respiration, neutralizing an acid with a base, and the setting of cement are all exothermic. Chemists record these reactions with a negative enthalpy change (ΔH < 0). Adding water to fresh quicklime in a lime pit grows so hot you can feel it from a metre away.
For example
Slake a lump of quicklime with water and the bowl grows too hot to hold; light the gas stove and the blue flame warms your whole kitchen — both give out heat.