Matter and energy are part of the Universe: matter gives it structure while energy gives it the capacity for change . When the Universe originated, everything was concentrated energy. As it expanded and cooled, matter was formed from energy.
An easy way to understand what is matter and what is energy is the following:
- a fruit and a table are matter;
- the ability of the fruit to fall off the table and hit an animal is energy; the ability of fruit to serve as food is energy.
- The capacity that a table (when burned) heats a room is energy; the ability of the table to break a window is energy.
|Definition||That which serves as a construction of nature.||Ability to do a job.|
|Constituents||Atoms, molecules, subatomic particles||Does not have|
|Types or forms|
|Unit of measure||Mass measurements: grams, kilograms, micrograms.|
Volume measurements: liters, cubic meters, milliliters.
|Examples||Water, air, sand, stones, planets, computer, paper, plants, animals.||Light, heat, magnetism, microwave waves, electricity.|
What is matter?
Matter is everything that is made up of subatomic particles and occupies space, even if it is extremely tiny: an electron, a proton, a neutron and everything that can be built from these is matter. For example, a table is made up of molecules that make up wood, iron nails and other elements, which are matter.
The term “matter” derives from the Latin mater which means “mother”. This means that matter is the “mother” of everything that surrounds us. For example, air, although we cannot see it, is matter, because it is made up of molecules of nitrogen, oxygen and other gases. The telephone, the computer, food, animals, buildings are all examples of matter.
The matter can absorb energy . A clear example of this is what happens when we put food in the microwave oven:
- the water inside the food absorbs the energy of the microwave waves;
- the energy in water is transferred to the rest of the food molecules.
That energy transfer is what causes the temperature to rise. cooking food.
Law of conservation of matter
The law of conservation of matter establishes that matter is neither created nor destroyed but is transformed. For example, when a piece of wood is completely burned in a closed system and the ash, carbon dioxide, and other compounds in the smoke are weighed, the sum of the masses will be approximately equal to the mass of the original piece of wood.
What are the characteristics of matter?
- It has mass: it is the amount of matter, for example, an electron has a mass of 9 x 10 -31 kg, a liter of water has a mass of 1 kg, the Sun has a mass of 1.9 x 10 30 kg.
- It has physical properties: within which density, electrical conductivity, melting or boiling point, volatility and hardness, among others, can be mentioned.
- It has chemical properties: matter can be transformed through chemical reactions, such as combustion, oxidation, decomposition.
What are the states of matter?
Matter comes in different forms or states:
- Solid : atoms and molecules are so packed that their movement is restricted.
- Liquid : the atoms and molecules of a liquid, although they are grouped together, can move freely.
- Gas : atoms and molecules are separated from each other and have no movement restrictions.
- Plasma : the atoms of gases are ionized. This is the state of matter for much of the Universe; we get it in the stars, in the lightning and in the auroras.
- Bose-Einstein condensate : when a set of atoms is at absolute zero (-273 ºC), they are so packed and immobile that they appear to be a single atom.
- Liquid crystals : it is the intermediate state of matter between solid and liquid without belonging to either of the two. We find it on flat screen televisions, computer screens and clocks.
What is energy?
The scientific definition of energy is the ability to produce work . In this sense, work is understood as any process where a body is displaced or deformed. For example, the ability of a stone on top of a mountain to fall and knock down trees in its fall, which would be work, is its energy.
Energy Conservation Law
The law of conservation of energy or the principle of conservation of energy states that the energy content of a system remains constant. That is to say, energy is neither created nor destroyed.
For example, a certain amount of gasoline has an X amount of chemical energy associated with it. When we start the vehicle, the energy in the gasoline is not destroyed but is transformed into kinetic energy to move the vehicle and thermal energy. The sum of the kinetic energy plus the thermal energy of the vehicle is equal to the amount of chemical energy of the gasoline, it cannot be neither more nor less.
What are the characteristics of energy?
- The amount of energy a body possesses is limited: the fruit on the table has an energy limited by its mass and by the distance from the table to the floor.
- Energy is transformed into its different forms: the chemical energy in gasoline is transformed into kinetic energy when you move a piston in the car.
- There are various sources of energy, such as the sun, wind and oil.
- It can be stored: chemical energy is stored in electric batteries, in hydroelectric dams the gravitational potential energy of water is stored.
Forms of energy
Energy can be presented in different forms:
- Potential energy : it is the energy associated with a body with respect to another reference body, for example, gravitational potential energy is the energy of a body with respect to its position on Earth, the higher it is, the more potential energy it has.
- Kinetic energy : it is the energy associated with the movement of bodies, for example when the water in a river makes rocks move it has kinetic energy.
- Mechanical energy : when a wagon is at the top of a roller coaster it has potential energy, which is transformed into kinetic energy as the wagon goes down and acquires a certain speed. In this case, the wagon has a mechanical energy, which is equal to the sum of the kinetic energy and potential energy.
- Radiant energy : light from the Sun reaches the Earth as radiant energy.
- Thermal energy : when we heat ourselves with a hot water bottle we are making use of thermal energy.
- Nuclear energy : when a nucleus of an atom breaks or fuses, it releases nuclear energy.
- Chemical energy : when glucose in cells is transformed into carbon dioxide, the energy found between the atoms of the molecule is released as chemical energy.
- Electrical energy : when the particles with a positive or negative charge move we are in the presence of electricity or electrical energy.
What is the relationship between matter and energy?
At the beginning of the 20th century, the theoretical physicist Albert Einstein (1879-1955) showed that matter is transformed into energy and that energy can be transformed into matter. This equivalence is known as the “theory of relativity” and is expressed in the famous equation:
E = mc 2 ,
where E represents energy, m represents mass, and c is the speed of light.
The best-known example of the transformation of matter into energy is the fusion reaction of hydrogen nuclei in stars. It is this energy in the Sun that sustains life on Earth.
Let us remember that in the origins of the Universe there was only energy, which was later transformed into matter. In an experimental way, energy is transformed into matter when a photon (a high-energy particle) passes through an atomic nucleus, producing a particle of matter (electron) and a particle of antimatter (positron).