What Is An Atom ?What Is An Atom
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What Is An Atom ?

An atom is the most fundamental and smallest part of a chemical element. It consists of a nucleus, which forms the central core. The nucleus comprises of protons and neutrons, and it is surrounded by electrons. The circulating electrons have a negative charge. The nucleus of an atom has a positive charge because the protons are positively charged, while the neutrons have to charge.

The number of protons in a nucleus of an atom determines the atomic number of a chemical element. The protons and neutrons have a larger mass compared to electrons.

The first model of an atom was created by a physicist named Ernest Rutherford in the year 1912. He was the first person to suggest that an atom was similar to the solar system. In this system, there was no gravity, so the attractive force that held the subparticles together was opposite electrical charges. According to Rutherford, the electrons orbited around the nucleus in a circular pattern.

However, Niels Bohr changed this theory. As per Bohr, the electrons orbited around the nucleus at precise distances, and these distances were labeled as shells. There are several shells around a nucleus and electrons have the ability to jump from one shell to another. However, in order for the electron to do this, it needs energy. Bohr claimed that when an electron absorbed a lot of energy, it would jump to a larger shell, while if it lose energy, it would jump to a smaller shell.

An atom has a mass or weight. This is known as the atomic mass or atomic weight. All protons, neutrons and electrons contribute to the atomic weight of an atom. However, when it comes to measuring the atomic weight of an atom in reality, physicists just take into account the number of protons and neutrons present in the nucleus of an atom. The number of neutrons in a nucleus of an atom can differ. So, most elements have many different atomic weights. Atoms that have equal number of protons, but different number of neutrons are known as isotopes, but they are part of the same element.

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What Is An Atom

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What Is Between The Atoms Or Molecules Of Each Of These Substances ?

What-Is-Between-The-Atoms-Or-Molecules-Of-Each-Of-These-Substances      Atoms are the fundamental ingredient of matter. All matter in this universe is made up of atoms. Atoms are known as the building blocks of matter just as the amino acids are building blocks of DNA. Atoms are microscopic in size and cannot be seen with naked eyes. Some matter present in the universe is composed of just one kind of atom. This type of matter is known as an element. Good examples of element are gold, silver, aluminum and oxygen. More..

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