Anomalous Properites of Beryllium

Anomalous behaviour refers to a behaviour that has a sort of variation from the order that is original or normal. This differentiation is from the other group members in terms of characteristics. Elements that exhibit anomalous behaviour have peculiar properties, and they make different compounds.

Beryllium is a chemical element. Its symbol is ‘Be,’ while its atomic number is 4. Amongst the alkaline earth metal group, it is the first member. Let us go into detail to discuss the anomalous behaviour of Beryllium and the reasons behind it. This way, you will be able to understand the peculiar behaviour of Beryllium better. 

Reasons For Anomalous Behaviour of Beryllium

The anomalous behaviour in certain elements, like the peculiar nature of Beryllium, is because of the following three factors-

Small size: In such elements, the size of atoms and ions is way smaller than others in the group.

High electronegativity: The first element is characterised by having the maximum amount of electronegativity.

Non-availability of d–orbitals: The higher members of the group possess d–orbitals and may use them to form bonds.

Physical Properties of Beryllium

Understanding the physical properties of Beryllium is essential when learning about the anomalous behaviour of Beryllium. The various physical properties of Beryllium are as follows:

• Its density is 1.85 g/cm3
• The melting point of Beryllium comes to about 1560 K (1287°C, 4476°F)
• The boiling point of Beryllium comes to about 2742 K (2469°C, 4476°F)
• Its heat of vaporisation is 297 kJ/mol
• Its heat of fusion is 7.895 kJ/mol
• The heat capacity of Beryllium is (25°C) 16.443 J/(mol/K)

Chemical Properties of Beryllium

When we discuss the anomalous behaviour of Beryllium, it is also important to know its chemical properties. The various chemical properties of Beryllium are as follows:

• Its CAS number is 7440-41-7
• The Thermal neutron cross-section of Beryllium comes to about 0.0090 barns/atom
• The Electrode potential of Beryllium is -1.70 V
• Its Ionic radius is 0.350 Å
• Its Electronegativity is 1.57
• The X-ray absorption edge of Beryllium is 110.68 Å
• The electrochemical equivalent of Beryllium is 0.168 g/A/h

The above chemical properties will help us in understanding the anomalous behaviour of Beryllium.

Peculiar Features of Beryllium

In comparison to the other elements in the block, Beryllium has peculiar characteristics because of the following:

• Tiny size
• Strong electronegativity
• High ionisation energy
• High polarising power

Compared to other elements in the group, below are the peculiar characteristics that help explain the anomalous behaviour of Beryllium:

• Among all the other alkaline earth metal atoms, it is the smallest of all.
• It is characterised by having the highest ionisation energy.
• This element has a coordinate number of 4. In contrast, other alkali metals are characterised by having a coordinate number of 6.

• The electronegativity of this element is higher in comparison to other elements.
• The boiling and boiling points of this element are higher in comparison to other alkali metals.
• This element lacks vacant d-orbitals in its valence shell.
• These elements result in the formation of covalent bonds, while other members facilitate the formation of ionic bonds.
• Unlike the other group members, this element does not react to water.

Difference Between Beryllium and other Alkaline earth  Metals

One way to better explain the anomalous behaviour of Beryllium is to know its differences with other alkaline metals. Below are the ways in which this element differs from other alkaline metals:

• Beryllium has higher melting and boiling points in comparison to all the other elements.
• This element does not decompose water, even when the exposure occurs at high temperatures. This is in contrast to other group elements.
• It does not impart colour when exposed to the flame test.
• Its oxide is amphoteric, while other elements’ oxides are basic in character.
• It is the hardest compared to all the other alkaline earth metals.
• Its compounds are mostly covalent in nature. This is in contrast to other elements that are mostly ionic in nature.
• There is no reaction of Beryllium with acids to result in the liberation of hydrogen. Once again, this property of Beryllium is in contrast to other group elements.

The above qualities bring out the anomalous behaviour of Beryllium.

Uses of Beryllium

Let us take a look at its various uses to understand the anomalous behaviour of Beryllium:

• Use of alloys of this element with copper or nickel is made to make various tools like- non-sparking tools, spot-welding electrodes, electrical contacts, springs, and gyroscopes.
• Mixing beryllium with any metal results in the formation of alloys. This results in increasing their thermal and electrical conductivity.
• Use of certain alloys of Beryllium is made as structural materials for communication satellites, spacecraft, missiles, and high-speed aircraft. 
• Its utilisation takes place in X-ray lithography. This is because this element exhibits transparency to X-rays.
• Its usage takes place in the production of various kinds of alloys.
• Its usage takes place in the storage of energy in electrochemical cells.

Conclusion

Anomalous behaviour refers to a behaviour that is characterised with variation from the order that is original or normal. In this context, there is a certain anomalous behaviour of Beryllium. There are certain physical and chemical properties that one must go through in order to explain the anomalous behaviour of Beryllium.

Beryllium has peculiar characteristics because of factors like- tiny size, strong electronegativity, high ionisation energy, and high polarising power. Compared to other elements in the group, Beryllium has certain peculiar characteristics. There is a difference between Beryllium and other alkaline metals.