The answers are An egg cooking is an endothermic reaction.
A candle burning and Plaster & water combining and becoming warm are exothermic reaction.
Salt being added to water, with no change in temperature neither endothermic nor exothermic reaction.
Explanation :
Endothermic reaction : It is a type of reaction in which energy is absorbed in the form of heat from the surroundings.
Exothermic reaction : It is a type of reaction in which energy is released in the form of heat from the system.
An egg cooking : In this process, the energy is absorbed in the form of heat.
A candle burning and Plaster & water combining and becoming warm : In both the process, the energy is released in the form of heat.
Salt being added to water, with no change in temperature : In this process, neither energy released nor absorbed.
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