Iwanted known how many of the reaction below is energy released

2

Explanation:

In two reactions energy is released.

1) C₆H₁₂O₆ + 6O₂    →    6H₂O + 6CO₂ + heat

It is cellular respiration reaction.It involves the breakdown of glucose molecule in the presence of oxygen to yield large amount of energy. Water and carbon dioxide are also produced as a byproduct.

Glucose + oxygen → carbon dioxide + water + 38ATP

2) 2H₂ + O₂   →    2H₂O  ΔH = -486 kj/mol

The given reaction is formation of water. In this reaction oxygen and hydrogen react to form water and 486 kj/mol is also released.

The reaction in which heat is released is called exothermic reaction.

Exothermic reaction:

The type of reactions in which energy is released are called exothermic reactions.

In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.

For example:

Chemical equation:

C + O₂   →  CO₂

ΔH = -393 Kj/mol

it can be written as,

C + O₂   →  CO₂ + 393 Kj/mol

Endothermic reactions:

The type of reactions in which energy is absorbed are called endothermic reactions.

In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.

For example:

C + H₂O   →  CO  + H₂

ΔH = +131 kj/mol

it can be written as,

C +  H₂O  + 131 kj/mol  →  CO  + H₂