Endothermic Reaction Chemistry Example 1

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Example 1

easy
Photosynthesis absorbs energy: 6CO2+6H2O+energyC6H12O6+6O26\text{CO}_2 + 6\text{H}_2\text{O} + \text{energy} \rightarrow \text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2. Why is this endothermic?

Solution

  1. 1
    In an endothermic reaction, energy is absorbed from the surroundings because products have higher potential energy than reactants.
  2. 2
    For photosynthesis, the reactants are CO2\text{CO}_2 and H2O\text{H}_2\text{O}; the product is glucose, which stores more chemical potential energy in its bonds.
  3. 3
    Since the system absorbs energy (sunlight) rather than releasing it, the enthalpy change is positive: ΔH>0\Delta H > 0.

Answer

ΔH>0(endothermic — absorbs energy)\Delta H > 0 \quad\text{(endothermic — absorbs energy)}
Endothermic reactions absorb energy from the surroundings. Plants use sunlight as the energy input for photosynthesis, storing that energy in the bonds of glucose.

About Endothermic Reaction

A chemical reaction that absorbs energy (usually as heat) from the surroundings, resulting in a decrease in surrounding temperature and a positive enthalpy change (ΔH>0\Delta H > 0).

Learn more about Endothermic Reaction →

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