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The Periodic Table should be rearranged, Scientists Propose

The periodic table should be rearranged according to a new proposal from scientists who proposed that elements should be assigned an MN value.

An MN refers to the Mendeleev Number derived from the atomic radius and electronegativity.

The new arrangement may be the light that guides researchers in discovering new elements to save scarce elements.

For over 150 years the periodic table as it existed was created by a Russian chemist, Dmitry Mendeleev, with nearly every aspiring chemists referring to it, its importance can’t be underestimated.

While one may think the periodic table isn’t subject to change, they should remember that scientists always find new ways of grouping information.

With the current being two scientists from Moscow, Russia, the birthplace of the periodic table, recently published a proposal for a new order.

While this may not be a shock to many scientists, it stands to reflect the changes that society has to endure with every generation.

In the 18th century, scientists knew the difference between an element and a compound i.e. an element is chemically indivisible for example hydrogen, oxygen 

A compound, on the other hand, is a combination of two or more elements with distinct properties of their original elements.

In the 19th century, scientists discovered the existence of atoms albeit with couldn’t be proved, however, by 1860, all known elements could be arranged in a list.

This list was in the order of their relative atomic mass e.g. hydrogen was 1 and oxygen 16, such a simple list was one-dimensional. 

Given that certain elements had similar chemical properties for example lithium, sodium and potassium.

Chemically similar elements could be placed next to each other which led to the creation of a two-dimensional table could be constructed. 

This arrangement gives birth to the periodic table, however, Mendeleev’s periodic table was derived from the observation of chemical similarities of certain elements. 

While it was until the early 20th century, when the structure of the atom had been established, after the development of quantum theory, which shone a light on the structure of the atom

With the new knowledge, scientist began arranging elements basing on their atomic number (the number of positively charged particles called protons in the atomic nucleus) rather than by atomic mass along with their chemical similarities

While the latter followed from the arrangement of electrons repeating in shells at regular intervals with most textbooks featuring the popular periodic table similar to the ones we see today by 1940.

This would have rested the challenge, as a simple search will return different versions of the periodic table. 

There are different versions of the periodic table namely; short versions, long versions, circular versions, spiral versions, including three-dimensional versions.

All the versions are different ways of conveying the same information with the disagreement on where some elements should be placed.

While the precise placement of certain elements depends on the particular properties that you want to highlight

The periodic table that gives priority to the electronic structure of atoms will differ from any other tables that use chemical or physical properties.

While these versions may look similar at the front sight, one will quickly notice the difference in key elements, for example depending on the criteria hydrogen may be in group 1 or group 17.

In the extreme case, however, one may choose elements to arrange elements without using their atomic number or electronic structure thus reverting to a one-dimensional list.

New proposal

Published in the Journal of Physical Chemistry by scientists Zahed Allahyari and Artem Oganov, proposed a new way to arrange the elements of the periodic table

Accordingly, building on work of others, the scientists propose assigning each element a Mendeleev Number (MN).

Although there are numerous ways of deriving such numbers, the proposal uses a combination of two fundamental quantities that can be measured directly.

These are the element’s atomic radius and electronegativity, the electronegativity is how strongly an atom attracts electrons to itself.

By arranging elements using this method, elements with similar, MN is closer to each other, however with the introduction of binary compounds, one can construct a two-dimensional grid.

Binary compounds are compounds composed of two elements, such as sodium chloride, NaCl.

This method makes it easier to predict the properties of binary compounds that haven’t been made yet. 

This makes it useful while searching for new materials which may be useful for future and existing technologies as compounds will be extended to have more than two elemental components.

For instance, using the new method one can identify elements that are becoming scarce as their future supply is uncertain.

By developing materials that replace the use of such elements, one may find the new periodic table valuable.

While we can see that periodic table is vital for researchers in their quest for essential new materials, periodic tables are also vital in education.

It is important to state that the new versions of the periodic table are not replacements for earlier depictions but rather serves to deepen our understanding of how elements behave.


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