Titanium, zirconium and hafnium, all belong to the D-block of Group 4 of Periodic table. These three elements are the only naturally occurring elements from group 4. Due to their existence in the same group, these three elements share somehow similar properties and are hard refractory metals. Below is the table comparing the physical properties of three Group 4 elements.
|
Name |
Titanium |
Zirconium |
Hafnium |
|
Melting Point |
1941 K |
2130 K |
2506 K |
|
Boiling Point |
3560 K |
4682 K |
4876 K |
|
Density |
4.507 g·cm−3 |
6.511 g·cm−3 |
13.31 g·cm−3 |
|
Appearance |
Silver metallic |
Silver white |
Silver gray |
|
Atomic Radius |
140 pm |
155 pm |
155 pm |
Occurrence:
Not only these three elements occur naturally, but also you can find them in a good amount on Earth's crust. If we compare the abundance of these metals, we can observe that the metal with the lowest atomic mass i.e. titanium is the one found most commonly. According to some survey reports, titanium has an abundance of 6320 ppm, Zirconium has 162 ppm whereas hafnium has the lowest of 3 ppm. Experts claim that you can find these three elements in heavy deposits of minerals in the sand near beach environment.
Production:
Most of you may be aware that the production of metals is a difficult process due to their reactivity. So, mostly the chemical reactions of these metals are done in vessels to avoid the natural formation of oxides, nitrites, and other metal compounds.
Applications:
This is the main part of the discussion of any material, the applications of metal depend on its properties. For instance, titanium from these three is the metal which is used in many applications requiring strength and durability. Titanium or its alloys are heat stable, corrosion resistant and lightweight. These properties make it suitable for use in various industries. Zirconium and hafnium are used in making nuclear reactors due to thermal neutron capture property of these metals. Furthermore, these metals significantly improve the properties of some alloys as well.
Hafnium or Zirconium?
It is challenging to differentiate between these two elements on the basis of chemical properties as their properties are quite similar. Scientists discovered a small amount of hafnium present in zirconium's samples. Hafnium is identified only by its physical properties which are somewhat different from zirconium's physical properties.
Biological Occurrences:
Any of the group 4 elements is not known to be present in any biological chemistry of living organisms. This may be because of their properties which make them unsuitable to be present in living organisms. They are hard refractory materials with very low aqueous solubility. According to research, it is known that these metals are highly toxic for biological chemistry.
Precautions and Final Statement:
Naturally, titanium is the only element here which is used in many applications in different fields. The positive point here is that from the process of extraction to production, there are no harmful effects of titanium. According to OSHA, there are cases of toxic effects of Zirconium and Hafnium but only some rare cases, like eye irritation, need medical attention.
For more information about advanced materials, please visit http://www.samaterials.com/