An\xa0atom\xa0is the smallest constituent unit of ordinary\xa0matter\xa0that constitutes a\xa0chemical element. Every\xa0solid,\xa0liquid,\xa0gas, and\xa0plasma\xa0is composed of neutral or\xa0ionized\xa0atoms. Atoms are extremely small, typically around 100\xa0picometers\xa0across. They are so small that accurately predicting their behavior using\xa0classical physics\xa0– as if they were\xa0billiard balls, for example\xa0– is not possible due to\xa0quantum effects. Current atomic models use\xa0quantum principles\xa0to better explain and predict this behavior.
Atoms are defined as\xa0“the basic building blocks of matter”.It is the smallest constituent unit of matter that posses the properties of the chemical element. Atoms don’t exist independently, instead, they form ions and molecules which further combine in large numbers to form matter that we see, feel and touch.Atoms are much too small to be seen; hence experiments to find out their structure and behavior have to be conducted with large numbers of them.\xa0From the results of these experiments we may attempt to construct a hypothetical model of an atom that behaves like the true atom.
The spreading of fragrance of incense stick from a corner to the whole room indicates that particles of matter keep moving from higher to lower concentration.
Atoms is the smallest components of an element, characterized by a sharing of the chemical properties of the elements and a nucleus with neutrons protons and electrons.