Chemistry is a science that studies matter, its transformations and the energy involved in these processes.But what is the definition of matter and energy?
Matter is everything that has mass and volume and therefore occupies space.With this concept in mind, we can say that air, metals, water, trees, grass, furniture, planets, stars, and even you are examples of matter; mbut feelings such as love, kindness, joy, jealousy, anger and so on cannot be considered matter.
As explained in the text What are all things made of?,all matter is made of atoms, very, very, very small particles!
The matter can go through physical and chemical transformations. Physical transformations do not change the composition of matter. An example is when we crumple the paper, it is still paper, only its shape has changed. On the other hand, chemical transformations alter the composition of matter, that is, the atoms of the material, which were linked together in a way, change places and form new substances. That's what happens when we burn paper.
Crumpled paper and burnt paper are, respectively, a physical and a chemical transformation
For these transformations to occur, it is necessary to win or lose energy.
explain what it is energy it's not easy, but generally it is defined the ability to produce some work, movement or action.
There are several types of energy. One example is when we receive energy in the form of heat from the Sun, the so-called Thermal energy. This heat is related to the movement of the particles that make up the materials. These particles vibrate, and the greater their movement, the higher their temperature. When two bodies are brought into contact, the one that is “hotter” (the one with the molecules vibrating faster) transfers energy to the other body that is “colder”. This transferred energy is called heat. In order to physically transform ice into liquid water, for example, it is enough to supply energy in the form of heat to the ice, which is our matter.
Energy is never created but transformed. See some examples of how this happens in practice:
THE chemical energy that exists in the components inside a stack is transformed into electricity, which, in turn, is used to turn on some device;
The chemical energy of gasoline is transformed into mechanical energy, that makes the car go;
The chemical energy within food is transformed in our body into energy that generates the work our body does in daily activities and also the heat that warms our body.
Here are some examples of different forms of energy:
Forms of energy: kinetic, potential, mechanical, chemical, electrical, magnetic, nuclear and thermal
By Jennifer Fogaça
Graduated in Chemistry
