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An atom is the most basic unit of a chemical element. It comprises two main parts. The first part is a very dense and very small core called a nucleus. Most of the mass of the atom is concentrated in the nucleus, and it is made up from protons and neutrons. The second part is a "cloud" of electrons, that move around the nucleus in various positions called "energy levels". The nucleus is made up of protons and neutrons. Protons and neutrons have roughly the same mass, although the neutron is slightly heavier, and they have a mass of about 1,840 times that of an electron. Protons and neutrons are collectively known as nucleons. Nuclei that contain the same number of nucleons are called isobars. The number of protons in the nucleus of the atom is what makes the chemical element unique. All atoms of Carbon, for example, contain six protons. Not all carbon atoms contain the same number of neutrons: the most common carbon atom ("Carbon-12") contains six protons and six neutrons, whereas another type ("Carbon-14") contains six protons and eight neutrons. Carbon-12 and Carbon-14 are known as isotopes of carbon. Neutrons, as the name suggests, are electrically neutral particles. They are needed in the nucleus in the right number, to make it stable. When the number of neutrons is fixed and the number of protons is allowed to change, the result is known as isotones of the nucleus. For example, a nucleus containing one proton and two neutrons ("Hydrogen-3", or Tritium) and a nucleus containing two protons and two neutrons ("Helium-4"), are known as isotones.
The neutron was discovered in 1932 by James Chadwick. It is stable when in the nucleus of an atom, but alone it decays into a proton, and electron and another particle called an antineutrino. Each proton has a positive electrical charge of one unit, so for an atom to be electrically neutral it must have the same number of electrons. These electrons do not "fall" into the nucleus, attracted by the protons. The reason is explained by Quantum Theory, which states that they may only exist at certain, specific energy "levels", or "shells". The first shell can hold two electrons, the second can hold eight electrons, and the nth can hold 2 x n-squared electrons. As a general rule, each shell is more stable when it is full. Shells that are more than half full tend to want extra electrons, and shells that are less than half-full tend to want to lose electrons. The number of electrons that an atom wants to gain or lose is called the "valency". Protons are what make a chemical element what it is. They reside in the nucleus along with neutrons, which are slightly heavier but which have no electrical charge. Electrons are much lighter, and revolve around the nucleus in "shells" of given energy levels. Each shell is more stable when it is "complete", and the degree of completeness gives every element its chemical bonding properties.
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How would you describe the Lewis dot structure for cation?
In a Lewis dot structure for a cation, an electron is removed from the neutral atom, resulting in a positive charge. The cation will have fewer electrons than the neutral atom, leading to a more compact Lewis dot structure with fewer electron pairs around the atom. The overall charge on the cation will be indicated by the addition of the positive sign.
What is the definition of spdf orbitals and how do they contribute to the electronic structure of an atom?
SPDF orbitals are a set of orbitals that describe the probability of finding an electron in a specific region around the nucleus of an atom. These orbitals are named after their shapes: s, p, d, and f. They contribute to the electronic structure of an atom by determining the energy levels and distribution of electrons within the atom's electron cloud. The number and arrangement of these orbitals help to define the overall behavior and properties of the atom.
What is the molecular structure of SCN- in terms of its Lewis structure?
The molecular structure of SCN- in terms of its Lewis structure consists of a central sulfur atom bonded to a nitrogen atom and a carbon atom. The sulfur atom has a lone pair of electrons, and there is a triple bond between the sulfur and nitrogen atoms.
What is the Lewis structure of CNH2?
The Lewis structure of CNH2 consists of a carbon atom bonded to a nitrogen atom, with two hydrogen atoms attached to the carbon atom. The nitrogen atom has a lone pair of electrons.
What is the Lewis structure of ch3cocn?
The Lewis structure of CH3COCN shows a carbon atom in the center bonded to three hydrogen atoms, one oxygen atom, and one nitrogen atom. The oxygen atom is double bonded to the carbon atom, and the nitrogen atom is single bonded to the carbon atom.
Which best describe the molecular geometry of nitrate ion?
It is a trigonal planar structure - the nitrogen atom in the center.
What is a model of the atom?
A model of the atom is a 3-D structure of the atom's structure.
What is the Model of atoms?
A model of the atom is a 3-D structure of the atom's structure.
How would you describe the Lewis dot structure for cation?
In a Lewis dot structure for a cation, an electron is removed from the neutral atom, resulting in a positive charge. The cation will have fewer electrons than the neutral atom, leading to a more compact Lewis dot structure with fewer electron pairs around the atom. The overall charge on the cation will be indicated by the addition of the positive sign.
Describe the structure and function of a fruit?
describe the structure of a fruit
What is the definition of spdf orbitals and how do they contribute to the electronic structure of an atom?
SPDF orbitals are a set of orbitals that describe the probability of finding an electron in a specific region around the nucleus of an atom. These orbitals are named after their shapes: s, p, d, and f. They contribute to the electronic structure of an atom by determining the energy levels and distribution of electrons within the atom's electron cloud. The number and arrangement of these orbitals help to define the overall behavior and properties of the atom.
How would you describe structure and bond in ceramics?
describe structure and bond in ceramics
What is the molecular structure of SCN- in terms of its Lewis structure?
The molecular structure of SCN- in terms of its Lewis structure consists of a central sulfur atom bonded to a nitrogen atom and a carbon atom. The sulfur atom has a lone pair of electrons, and there is a triple bond between the sulfur and nitrogen atoms.
Why were Niels Bohr's ideas important to the understanding of the structure of the atom?
What was proven wrong about the structure of Niels Bohr atom
Of atomic structure describe the most probable location of an electron in relation to the nucleus of an atom?
In a shell at a distance form the atomic nucleus. The Electron Cloud
What is an appropriate model that has been developed to describe atomic structure?
The Bohr model is an appropriate model that has been developed to describe atomic structure. In this model, electrons orbit the nucleus in discrete energy levels or shells. It helps explain how atoms absorb and emit light energy.
What does the atomic number describe about an atom?
The number of protons in the nucleus of an atom
