Elastic potential energy can be stored in rubber bands, bungee cords, trampolines, and springs. The amount of stiffness the rubber band or spring has affects its amount of elastic potential energy that is present in the object. The animation below shows springs with 100 gram weights on each.

Click on the release button to see which spring has more potential energy.

Chemical Potential Energy

Chemical potential energy is energy stored in chemical bonds. Energy is released when bonds are broken, and substances undergo chemical changes. The weaker the chemical bond, the more energy that is present between the bonded atoms.

A battery has chemical energy, which can be transformed to light and heat energy when it is a part of an electrical circuit. Wood, coal, and gasoline all have potential energy that also can be transformed into heat and light energy when they burn or undergo the chemical change called combustion. Even the food we eat contains energy stored as chemical energy.

For example, during respiration glucose sugar is broken down to release energy. During respiration, chemical changes take place, and energy is released.

The formula for respiration is as follows:

The structure of the glucose molecule looks like the image below. Each of the lines represents a chemical bond. If the chemical bonds are broken energy is released.

Source: Glucose, BBC