What causes exothermic reactions?

Answer 1

Exothermic Reactions occur when a chemical reaction releases energy in the form of heat. This is the opposite of endothermic reactions in which energy is absorbed. In exothermic reactions, usually the reactants have a higher energy level than the products do. These reactions are typically caused when the enthalpy change value is a negative number (energy used in bond breaking reactions − energy released in bond making products). Combustion is an example of a exothermic reaction.

Answer 2

Exothermic reactions release heat to their surroundings. They occur when the total energy of the products is lower than the total energy of the reactants, resulting in excess energy being released as heat. This can be due to the formation of stronger bonds in the products or the release of strain in the reactant molecules.

Answer 3

A chemical reaction is when bonds are broken are remade to form something else.

First, you start off with the initial substances you start off with are known as the reactants.

Example) AB + CD
In this example, AB is one of your initial bonded substances and CD is your second initial bonded substances, which are known as reactants.

Between the bonds of AB and CD is a lot of potential energy. But then energy, known as the activation force, is applied to the bonds. This activation energy causes the bonds to enter a transition state. In the transition state, the bonds are undermined and broken.

Then after the bonds are broken, the amount of energy begins to decrease again.

Then the bonds reform. So now you get AC + CD. This is called your product.

This is how an exothermic reaction occurs. But keep in mind that in order for a chemical reaction to occur, the reactants must collide with sufficient energy and proper orientation, otherwise nothing will happen.

Answer 4

Different chemical substances contain different amounts of energy in their chemical bonds. When a chemical reaction occurs the amount of energy in the reactants is never quite the same as it is in the products, and since energy is conserved in all processes, the chemical bonds must either gain energy from their environment (an endothermic reaction) or release energy into it (exothermic reaction). For example, the bonds in hydrogen and oxygen gasses contain more energy than the bonds in the same amount of water. So when hydrogen and oxygen react to form water they must release energy in the form of heat and light.

Answer 5

If the molecules of the results of a chemical reaction have lower inherent energy than the input (fuel) molecules, then the excess energy is "released" -

thus "exothermic"

Answer 6

two different types of of chemicals or and solutions mixed together make an exothermic reacting like water and CaO they use this reaction in slef-heating cans.