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Questions
Why is respiration considered an exothermic reaction? Explain.
Explain why respiration is considered as an exothermic reaction. Give the chemical equation for this reaction.
Solution 1
Respiration is considered as an exothermic reaction because, in respiration, the oxidation of glucose takes place, which produces large amount of heat energy.
\[\ce{C6H12O6(aq) + 6O2(g) -> 6CO2(g) + 6H2O(l) + energy}\]
Solution 2
We get this energy from the food we eat. During digestion, food is broken down into simpler substances. For example, rice, potatoes and bread contain carbohydrates. These carbohydrates are broken down to form glucose. This glucose combines with oxygen in the cells of our body and provides energy. The special name of this reaction is respiration. Thus, respiration is an exothermic process because energy is produced during this process.
\[\ce{C6H12O6(aq) + 6O2(aq) -> 6CO2(aq) + 6H2O(l) + energy}\]
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