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Question
Explain the term with examples.
Endothermic reaction
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Solution
Endothermic reaction:
An endothermic reaction is any chemical reaction that absorbs heat from its environment. The absorbed energy provides the activation energy for the reaction to occur. A hallmark of this type of reaction is that it feels cold.
A good example of an endothermic reaction involves dissolving a salt. The salt doesn't have to be table salt, and the solvent doesn't need to be water.
- The reaction of barium hydroxide octahydrate crystals with dry ammonium chloride
- Dissolving ammonium chloride in water
- The reaction of thionyl chloride (SOCl2) with cobalt(II) sulphate heptahydrate
- Mixing water and ammonium nitrate
- Mixing water with potassium chloride
- Reacting ethanoic acid with sodium carbonate
- Photosynthesis (chlorophyll is used to react carbon dioxide plus water plus energy to make glucose and oxygen)
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