Question

With the help of balanced chemical equation explain why respiration is considered as an exothermic reaction

Answer 1

Respiration is an exothermic reaction because during respiration Carbon dioxide present in food breaks down to form glucose. This glucose combines with Oxygen and releases high amount of energy.

The reaction involves:

C6H12O6 + 6O2 ----->6CO2 + 6H2O + Energy

Here, C6H12O6= Glucose, O2= Oxygen Gas, CO2= Carbon dioxide and H2O= Water.

Answer 2

Answer :

Respiration refers to the overall process by which organism is abstracted from air and is transported to cells for the oxidation of organic molecules (glucose) while carbon dioxide and water, the product of oxidation, are returned to the environment. During digestion, carbohydrates, we take as food, are broken down into glucose. When we breathe in air, the oxygen enters our lungs. It bind itself with the haemoglobin present in red blood cells and is carried to millions of cells present on the body. Here, glucose 'burns', i.e., gets oxidized to produce carbon dioxide and water be liberation of heat (energy).

Chemical reaction :

$\sf \small C_{6} H_{12} O_{6} (s) + 6O_{2} (g) \longrightarrow 6CO_{2} (g) + 6 H_{2}O(\ell) + 2820 kJ$