A mixture of hydrogen gas and oxygen gas are ignited and the following reaction occurs: Hydrogen + Oxygen = Water + Energy. Is this an Endothermic or Exothermic reaction and why?
see below.
To determine if this reaction is endothermic or exothermic, we need to consider the energy change during the reaction.
In an endothermic reaction, energy is absorbed or taken in from the surroundings. This means that more energy is required to break the bonds of the reactants than is released by the formation of the products.
On the other hand, in an exothermic reaction, energy is released or given off to the surroundings. This means that more energy is released during the formation of the products than is required to break the bonds of the reactants.
In the given reaction, hydrogen and oxygen combine to form water, and energy is released in the process. This indicates that the reaction is exothermic because energy is being given off or released.
To verify this, you can also look at the energy change of the reaction. One way to measure this is through the enthalpy change (∆H) or heat of reaction. If the ∆H value is negative, it indicates an exothermic reaction. In the case of the combustion of hydrogen gas and oxygen gas to form water, the ∆H value is negative, further confirming that it is an exothermic reaction.
In summary, the given reaction of hydrogen and oxygen to form water and release energy is an exothermic reaction because more energy is released during the formation of products than is required to break the bonds of the reactants.