Q.9: What does one mean by exothermic and endothermic reactions? Give examples. | Unit1 Chemistry NCERT solution-Grade-10

Q.9: What does one mean by exothermic and endothermic reactions? Give examples.

 

Answer:-

Exothermic reactions: Those reactions in which energy is released in the form of heat are called exothermic reactions.

Examples –

(1) All combustion reactions e.g.
CH4 + 2O2 —> CO2 + 2H2O + Heat
(2) Thermite reactions e.g.
2Al + Fe2O3 —> 2Fe + Al2O3 + Heat
Combinations are generally exothermic in nature. The decomposition of organic matters into compost is an example of exothermic reaction.

Endothermic reactions: Those reactions in which energy is absorbed are called endothermic reactions. Examples –

 
X+Sc+Chp1+Q9
also, the reaction of photosynthesis –
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