Energy and Matter

Energy Energy – the ability to do work or cause change. – Like matter, energy is never created or destroyed in chemical reactions. Energy can only be transformed – changed from one form to another.

Forms of Energy Forms of energy, related to changes in matter include thermal energy, chemical energy, electromagnetic energy, and electrical energy.

Thermal Energy Thermal Energy – is the total energy of all the particles in an object. Temperature – is a measure of the average energy of random motion of particles of matter.

Temperature and thermal energy are NOT the same thing, but temperature is related to the amount of thermal energy an object has.

Thermal Energy continued…… Thermal energy always flows from warmer matter to cooler matter.

Endothermic Change Endothermic Change – a change in which energy is taken in.

Exothermic Change Exothermic Change – releases energy. – Example: Combustion releases energy in the form of heat and light.

Chemical Energy Chemical Energy – Energy stored in chemical bonds between atoms. – Food you eat – Gasoline – Cells of your body

Chemical Energy continued…. When a chemical change occurs, chemical bonds are broken and new bonds are formed. If change is exothermic, some of the chemical energy is transformed and released in a variety of other forms.

Electromagnetic Energy Electromagnetic Energy – a form of energy that travels through space as waves. – Sun – visible light

Electrical Energy The energy of electrically charged particles moving from one place to another. Electrons move from one atom to another in many chemical changes.