Chemistry

Structure of Matter

• The things in our environment can be classified into two main categories as matter and energy. Those that occupy space and have a mass are called matter.
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  • Atoms are the building units of matter.
  •  The atom is composed of subatomic particles.
  • Of them, protons, electrons and neutrons are the main subatomic particles.
  • The electron is a negatively charged particle. 
  • Proton has a positive charge while neutrons have no charge. 
  • With the identification that particles called electrons, protons and neutrons constitute matter, and as a result of the effort taken to describe how those particles are organized in matter, the atomic model was introduced.
  • According to the nuclear model put forward by Ernest Rutherford in 1911, there is a very small area called nucleus at the center of the atom.