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From Rafaelrz:
In fluids part of the energy is stored in the molecule's:
Kinetic Energy.
Rotational Energy.
Vibration Energy.
Electronic Energy.
In solids the first two are excluded.
Another part of the energy is stored in the chemical bonds
between the atoms that form the molecule.
A large amount of energy is stored in the forces ("Strong
Forces) that keep the nuclear particles together in the atoms
nucleus (Nuclear Energy).
Heat
Chemical Energy
Chemical energy is stored within the bonds between atoms and molecules in matter. When these bonds are broken through chemical reactions, such as combustion, this stored energy is released in the form of heat and light.
The form of energy stored in matter is often referred to as potential energy. This includes the energy stored in the bonds between atoms and molecules, as well as the mass energy equivalent calculated by Einstein's equation, E=mc^2.
Chemical energy.
Energy is responsible for binding particles together in matter through forces like electromagnetic interactions. It also determines the motion and temperature of particles within matter. Energy can be stored in matter in various forms, such as kinetic energy of particles or potential energy stored in chemical bonds.
An electron is a small particle of matter where energy can be stored. It carries a negative charge and plays a fundamental role in electricity and magnetism.
Chemical energy.
The term for organic matter that contains stored energy is biomass. Biomass can be used as a source of renewable energy through processes such as combustion or fermentation.
Organic matter that contains stored energy is called biomass. It can be converted into usable forms of energy such as biofuels through processes like combustion or fermentation.
The energy stored in coal that is converted to heat is chemical energy. Of course coal, like any other matter, also has stored nuclear energy.
The term for stored energy that matter possesses related to its position or chemical composition is potential energy. It is energy that an object has because of its position or state, such as gravitational potential energy or chemical potential energy.