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elas
Is there a formula for calculating the atomic or covalent radii of elements, isotopes or ions?
elas said:...There is also the fact that we do not know what the various forces or mass and charge really are, or why they exist, but that is not a chemistry forum subject.
I have ordered a copy of 'Bonding and structure' by N W Alcock, but if there are other books you would recommend please let me know. My subject is 'what causes of the structure of fundamental particles and atoms to exist in their particular form'.
I am somewhat puzzled by the fact that the most detailed explanation of the current teachings seems to be found in the chemistry forum and in books on chemistry, while the various physics forums and their multitude of books show little interest in anything other than predictive theories.
Neither physicist or chemist seem prepared to acknowledge how little we know about structure, both being prepared to rely on predictive theories, without being unduly concerned at our lack of fundamental knowledge.
maverick280857 said:Coming back to your question, I would repeat the statement made in my first post: that there exists no single "formula" to compute the radius of an atom. Firstly, an atom has no unique boundary for you to place a marker and make a measurement--this is of course due to quantum mechanics. Secondly, all our observations are made on samples containing a large number of atoms since it is experimentally very difficult to obtain a single atom. Hence, radii measurements are conducted on samples of atoms and then averaged out to give you an estimate.
This "average" value is not really the actual value as according to quantum mechanics, the electron cloud may smear even farther than the confines of a conventional boundary surface (the orbital) it existed in. The actual value is time variant and it would be difficult for us to base conclusions about the atoms (their properties) on time variant quantities. So the average is your best bet :-), though you must understand that the orbital is a region in space where the probability of finding the electron is about 95%--so average values are not grossly incorrect for explaining a large number of propositions (and exceptions) in general chemistry.
To calculate the atomic radius of an element, you can use the following formula: atomic radius = 0.5 x (distance between two nuclei in a diatomic molecule). This distance can be found in scientific literature or databases.
Atomic radius refers to the size of an atom when it is in its neutral state. Covalent radius, on the other hand, is the size of an atom when it is bonded to another atom in a molecule. Covalent radii are typically smaller than atomic radii due to the attraction between the bonding atoms.
The atomic and covalent radii generally decrease from left to right across a period (row) on the periodic table. This is due to the increase in the number of protons and electrons, which leads to a stronger attraction between the nucleus and the outermost electrons, making the atoms smaller. The radii increase down a group (column) due to the addition of new energy levels as you move down the periodic table.
No, the atomic or covalent radius cannot be negative. These radii represent the distance between the nucleus and the outermost electrons, and distance is always a positive value.
The formula for calculating atomic or covalent radii is a simplified approximation and may not accurately represent the actual radii of atoms. This is because the size of an atom can vary depending on its bonding and the environment in which it is found. Additionally, the values of atomic or covalent radii may vary slightly depending on the source and method used for calculation.